Specifically what Hume is saying here is that we can have no idea of existence, an idea that we might join to another idea, as a way of having the idea of something existing. It's about our conceptions, not logic, not language. Might Hume have taken another line? Might he, for instance, have said, that to imagine an object differs from imagining it as existing in that the latter is more vivid, or more complete, or something like this? There would still, I think, be no distinct conception of existence. Even if he were to say that conceiving an object as existing is the usual conceiving but accompanied by some particular feeling, that leaves the conception the same, and this is Hume's only point.

...

Now since nothing is ever present to the mind but perceptions, and since all ideas are deriv'd from something antecedently present to the mind [ argued earlier ]; it follows, that 'tis impossible for us so much as to conceive or form an idea of any thing specifically different from ideas and impressions.

That is, when we try to conceive the 'external objects' that occasion our perceptions, we have nothing but perceptions to work with — we have no other material with which to construct a conception of 'object', no material that would make such a conception a distinct sort of thing from a perception.

Or: try as you may to conceive, for once, of an external object, itself, you will only produce another idea, an idea derived from previous perceptions, impressions and ideas. It's all your mind can do; there is only one sort of object available to your mind, a perception, and any attempt to bring some other kind of object, whatever it may be, into your mind will fail utterly or substitute an idea of that other kind of object. — Srap Tasmaner

I don't think Hume is correct in these points. We can pull from the imagination, a completely imaginary conception of what it means to exist, or a completely imaginary conception of what it means to be an external body, without reference to sensation. This is what happens with so-called pure mathematics, mathematicians come up with completely imaginary ideas about objects, and orders, without referencing perceptions.

In reality, we generally do reference perceptions in order to validate these conceptions, but it's not necessary to the conceptions. So we really dream up imaginary conceptions independent from our perceptions, and then we relate them to each other, conceptions to perceptions, in an attempt to validate each other. But the validation is not just one way, in the sense that the conceptions must conform to the perceptions, because sometimes conceptions can prove the perceptions to be wrong. Therefore we cannot assume, as Hume seems to, that all conceptions are based in perception.

Are you remaining within the chapter? — Manuel

Yeah, except for going back to Part II Section VI for the existence stuff.

I think that some of this may be alleviated once you get to the part in which he discusses the imagination. — Manuel

Some of what?

So far as I can see, he's still talking about our perceptions of the object, and then the problem is how do these perceptions tell us something about the existence and continuity of these objects ("body"), which "we must take for granted." — Manuel

Two points:

1. Something else conspicuous by its absence is the word "representation"; when he covers this material in the Enquiry he uses phrases like "perception or representation", but there's no such suggestion here. The word might be in there somewhere, but there doesn't seem to be much use made of the idea; the whole flavor of the account is causal, mechanical. Whatever 'occasions' (Hume's word) our perceptions, they appear from mind's point-of-view as sui generis.

2. Even if there are principles connecting objects to each other 'out there', beyond our minds, those principles apply to objects, not to our perceptions of them — thus we must have our own mental principles, which will apply to our perceptions, in order to conceive something like causality. Similarly, even if there are principles connecting the presentations of an external object to mind — namely, the distinctness and continuity of the object — it will do us no good: we need principles that will relate certain perceptions to each other.

Hume thinks we can analyze the principles governing the behavior of perceptions, but if there are analogous principles governing the behavior of external objects, we cannot know what they are and cannot analyze them. We might as well presume there are no such principles, it makes no difference.

Ultimately, Hume is trying to convince his perceptions that they are perception. — Richard B

As the above makes clear, I don't think so. I think Hume's idea is that it's irrelevant what the source of our impressions is; however they come to mind, they are now mental phenomena, and whatever principles govern the relations among mental phenomena must be mental principles, not such principles as we imagine govern the behavior of external objects.

He doesn't really need the tyranny of Nature here, does he? The sceptic is not admitting anything of any consequence. — unenlightened

I'm still unclear on this. All I've come up with so far is that Hume believes he must provide some explanation for our universal assumption that there are distinct, continuing, external objects. Whether it's true is just not at issue; we have no reason to believe it (he says) but we do, so he believes he must explain why we hold this unjustified view.

The idea of existence conjoined with the idea of any object makes no addition to it, but existence conjoined with the idea of any object adds everything to it. — unenlightened

I mean, it's clear that there's a difference between imagining there's a chocolate cake in the kitchen and believing there is. Hume has already dealt with that difference, earlier in the book. What else is there to say?

I've always thought the logical argument against existence being a predicate was convincing: an object existing and not existing must have the same properties, else existing is not what distinguishes them.

I'm not sure what good it is, but Hume's point that to imagine something is to imagine it existing — that's pretty interesting. It actually sounds plausible, but of course you can't tell the difference! It's a strange thought that undermines itself.

As the above makes clear, I don't think so. I think Hume's idea is that it's irrelevant what the source of our impressions is; however they come to mind, they are now mental phenomena, and whatever principles govern the relations among mental phenomena must be mental principles, not such principles as we imagine govern the behavior of external objects. — Srap Tasmaner

The study of physics, energy, mass, space and time, is how we make prediction of the objects around us. Not the study of mental phenomena.

Of course you can disagree with Hume; but can you make a case against his view?

For instance, Hume's view as I'm presenting it (not sure I'm getting him right) could be tweaked to more closely resemble relatively mainstream psychology: to claim some physical law governs the behavior of external objects is to describe our expectations about their behavior, which will for us just be particular sensory experiences and that's what we're actually predicting.

There's (not coincidentally) a similar perspective flip in the subjective account of probability (and thus of statistics).

So what's the critique of such views beyond mere disagreement?

Some of what? — Srap Tasmaner

You're doubts about him depending on perceptions to speak about the continuity of external objects when not perceived. His gives a lot of role to the imagination.

The word might be in there somewhere, but there doesn't seem to be much use made of the idea; the whole flavor of the account is causal, mechanical. — Srap Tasmaner

Yes. I think he has in mind something like mechanical, but also something like an instinct, a phrase he doesn't appear to use in this chapter. Perceiving is like breathing or seeing, we can't not have perceptions.

Even if there are principles connecting objects to each other 'out there', beyond our minds, those principles apply to objects, not to our perceptions of them — thus we must have our own mental principles, which will apply to our perceptions, in order to conceive something like causality. — Srap Tasmaner

This is tricky. He's focusing here on our reasons for believing in them, but I keep going back to the "for granted" comment. The tension here, if there is one, is that there seems to be no connection, under these arguments from perceptions to those bodies we take for granted. But when he leaves philosophy and goes to "the vulgar system" (vulgar meant ordinary people, not an insult as it taken today), there are no problems about our recognizing and interacting with the world.

we need principles that will relate certain perceptions to each other. — Srap Tasmaner

VERY perceptive. This is one of the reasons he gives in the Appendix for, essentially stating that his system fails, or as he puts it "my hopes vanish". This is one of the things he cannot account for, how perceptions relate to each other. The other being that we really do perceive continuity in the objects. In other words, he has used these two principles: the uniting principle and the continuity principle (my terminology, not his), without being able to justify them, but he isn't able to renounce either of them.

That goes way beyond this chapter in terms of pages, but it's connected. Very, very interesting. And humbling too, to be able to say that about one's own system.

The word might be in there somewhere, but there doesn't seem to be much use made of the idea; the whole flavor of the account is causal, mechanical. — Srap Tasmaner

Yes. I think he has in mind something like mechanical, but also something like an instinct, a phrase he doesn't appear to use in this chapter. Perceiving is like breathing or seeing, we can't not have perceptions. — Manuel

we need principles that will relate certain perceptions to each other. — Srap Tasmaner

VERY perceptive. This is one of the reasons he gives in the Appendix for, essentially stating that his system fails, or as he puts it "my hopes vanish". This is one of the things he cannot account for, how perceptions relate to each other. The other being that we really do perceive continuity in the objects. In other words, he has used these two principles: the uniting principle and the continuity principle (my terminology, not his), without being able to justify them, but he isn't able to renounce either of them. — Manuel

I agree that he had instincts in mind. My interpretation of his thought: though to a far smaller (else, more generalized) extent than lesser animals, humans are nevertheless inescapably driven by instincts - including those of what you’ve termed the unifying principle and the continuity principle of perceptions, both to my mind being subsumed by reasoning in general.

To my reading he briefly addresses our faculties of reasoning being instinctive at the very end of a previous chapter, Part III Section XVI (Of the reason of animals), starting at the bottom of page 179 [boldface mine ... as well as any potential typos]:

“Nothing shews more the force of habit in reconciling us to any phenomenon, than this, that men are not astonish’d at the operations of their own reason, at the same time, that they admire the instinct of animals, and find a difficulty in explaining it, merely because it cannot be reduc’d to the very same principles. To consider the matter aright, reason is nothing but a wonderful and unintelligible instinct in our souls, which carries us along a certain train of ideas, and endows them with particular qualities, according to their particular situations and relations. This instinct, ‘tis true, arises from past observation and experience; but can any one give the ultimate reason, why past experience and observation produces such an effect, any more than why nature alone shou’d produce it? Nature may certainly produce whatever can arise from habit: Nay, habit is nothing but one of the principles of nature, and derives all its force from that origin.”

Very many humans are very off-put today when told that we humans are to significant extents instinctively driven - and this is well after our knowledge of evolution. I can easily envision that Hume didn't greatly dwell on this notion in his writings due to the audience of his time.

Of course you can disagree with Hume; but can you make a case against his view?

For instance, Hume's view as I'm presenting it (not sure I'm getting him right) could be tweaked to more closely resemble relatively mainstream psychology: to claim some physical law governs the behavior of external objects is to describe our expectations about their behavior, which will for us just be particular sensory experiences and that's what we're actually predicting.

There's (not coincidentally) a similar perspective flip in the subjective account of probability (and thus of statistics).

So what's the critique of such views beyond mere disagreement? — Srap Tasmaner

The critique is that this way of looking at things posits sensory experience as the cause of all mental ideas. Thinking, mind, ideas, and mental activity in general, is represented as being dependent on perception, therefore caused by perception. This perspective is strongly determinist, and does not allow for the reality of free will. Free will requires that ideas may come from a source independent from bodily influence (sense perception).

The offending part is this:

There is no claim that perceptions are the only kind of objects, or that all objects are really perceptions, but only that the only kind of object in our minds is perception.

The farthest we can go towards a conception of external objects, when suppos'd specifically different from our perceptions, is to form a relative idea of them, without pretending to comprehend the related objects. Generally speaking, we do not suppose them specifically different; but only attribute to them different relations, connexions and durations. But of this more fully hereafter.

And that's the pointer to our section, Part IV Section II, where he will refer back to this section: — Srap Tasmaner

I haven't found where you've taken this quote, but I do not think you interpret it correctly. You represent the conceptions of external objects as being dependent on, or necessarily caused by, perceptions. This denies the possibility that a representation of external objects could be entirely fictitious, imaginary, created completely by the mind. But I do not think that Hume intends this, he seems to give imagination a very strong role.

To be fair to Hume now, he seems to be more inquisitive of this perspective, that perception plays a necessary role in the conception of external objects, rather than firmly attracted to it. That's why he starts with the premise that the continued existence of external objects, cannot be justified, it's something that we just take for granted. So he moves then, to ask what causes us to believe in continued and distinct existence, what causes us to take it for granted, rather than asking what causes continued and distinct existence itself. And this leads him toward imagination.

We may, therefore, conclude with
certainty, that the opinion of a continu’d and of a distinct
existence never arises from the senses — 192

It's a funny turn around, and a bit deceptive if we don't analyze and understand the position properly. If we truly took continued existence, (what I call temporal persistence) for granted, as a real thing, then we'd move to inquire into the cause of continued existence. But Hume is taking the skeptical position, saying the idea is not justified by our perceptions, and that it's an idea that we take it for granted even though we do not have proper justification for it. This inclines him to ask what causes us to believe in continued existence, rather than to ask what causes continued existence. And it is within this hidden premise, that a belief must have a cause, if we accept it, that Hume could actually lead us to negate free will, for the sake of determinism. That is, if we accept Hume's notion that the belief in continued existence must have a cause, rather than attributing this belief to free will, and accepting continued existence as real, something to be taken for granted, and searching for the cause of it.

It's best that you give proper context to "continu'd existence". This is what is expressed by Newton's first law, the law of inertia. In general terms, this law states that what has been, in the past, will continue to be in the very same way, into the future, unless caused to change. This is the temporal continuity of existence, inertia, or temporal persistence. This law states that staying the same as time passes is to be taken for granted, and it says that change requires a cause. Notice that the reversal of this law would take change for granted (process philosophy, Heraclitus), and state that staying the same (continued existence, or temporal persistence), requires a cause. Though Newton stated his first law in such a way as to take continued existence (temporal persistence, inertia) for granted, he is also known to have said that this law requires the Will of God for its truth. That is to say, that continued existence, or inertia, is caused by God's Will. So his first law, the law of inertia, takes the Will of God for granted, in order for it to be a valid "law", effectively denying God the capacity of free will to alter what we know as continued existence, setting up the grounds for determinist physics.

Yes, that's a great quote from his Treatise. That's exactly right, or at least, that's how it looks like to me as well. This is somewhat paradoxical, given his reputation and thrust of his thought, an argument for innate faculties, as he puts what you quoted in his Enquiry:

"...and in which they improve, little or nothing, by the longest practice and experience. These we denominate Instincts, and are so apt to admire, as something very extraordinary..."

Italics mine.

He was speaking of animals in this quote, but it applies to us too. After all, Hume was a naturalist. And like you say, he had to be somewhat cautious in what he said at his time.

You represent the conceptions of external objects as being dependent on, or necessarily caused by, perceptions. This denies the possibility that a representation of external objects could be entirely fictitious, imaginary, created completely by the mind. — Metaphysician Undercover

Not what I intended at all. I was, I thought, following Hume's usage in using the word 'perception' to cover both impressions and ideas; so a perception is something present to the mind, of whatever source, a perceiving that is done 'by the mind's eye' we might say.

It's best that you give proper context to "continu'd existence". This is what is expressed by Newton's first law, the law of inertia. — Metaphysician Undercover

Here's what I think Hume is saying.

As I watch the birds flitting about in my front yard, I have an impression of a bird first here, then there, then there, as it moves from tree to tree. On a naive view, we might say there is a body, some force is applied to that body, and thus the body is caused to move through the air. We can see in the bird's flight inertia, which carries it along a certain path (modified by gravity and drag) until it flaps its wings again, adding a new vector which modifies its course, and so on.

Now consider me watching this: I have an impression of the bird; that impression is replaced by a different one with the bird elsewhere. Did my impression of the bird move? Of course not; I'm sitting on my porch and all my impressions of the bird are in the same place. Did my impression of the bird acquire an inertial force carrying it from one place to another? Perforce, no: my impression did not move; my impression had no such force applied to it.

Whatever connects my impression of the bird in one place to my impression of the bird in another place cannot be the same sort of physical law (inertia) that connects the bird being first in one place to its a moment later being in another. Newton's laws may apply to external objects that occasion my impressions (if there be such things) but they clearly do not apply to my impressions themselves.

I think it's a line of thought something like this that lies behind Hume's arguments. Habit, custom, instinct, imagination, association, all these sorts of things will fill, within the mental realm, the role that Newton's laws fill in the physical realm, laws that connect one event to another.

And of course once started down this path, it'll become clear that even belief in the existence of distinct and persistent external bodies is also down to the operation of such mental laws. Hume recognizes that it is the science of human nature that must underwrite all the other sciences, including Newton's physics.

like an instinct, a phrase he doesn't appear to use in this chapter. — Manuel

That's exactly right, or at least, that's how it looks like to me as well. — Manuel

I’ve found another supporting quote from within the chapter (Part IV Section II, page 214). This is in introduction to the notion of double existence: to roughly paraphrase, here he articulates the opinion that our instinctive awareness of resembling perceptions being continued, identical, and independent is indicative of the external existence of objects in the world whereas our reasoned awareness that our perceptions are all dependent, interrupted, and different is indicative of our minds’ internal existence. (Emphasis on the former external existence being inferred by us on account of what our instinctive awareness informs us of – this in contrast to our internal existence which is inferred from reasoning regarding our perceptions.)

“There is a great difference betwixt such opinions as we form after a calm and profound reflection, and such as we embrace by a kind of instinct or natural impulse, on account of their suitableness and conformity to the mind. […] Thus tho’ we clearly perceive the dependence and interruption of our perceptions, we stop short in our career, and never upon that account reject the notion of an independent and continu’d existence. […]”

boldface mine.

This is somewhat paradoxical, given his reputation and thrust of his thought, an argument for innate faculties, — Manuel

Yes, maybe. Still, what I’ve read about Hume is often quite different than what I gathered from directly reading Hume. For one example, to me, Kant borrowed from Hume rather than debunking him. Hence, imo, Kant’s categories are a subset of Hume’s natural impulses (instincts) which Kant worked out to far greater extents - and to which Hume's epistemology of causation still applies. Likewise, Kant’s noumena are Hume’s objects of external existence which, again to paraphrase Hume, resemble internal perceptions due only to fancy but not due to any reason to so infer. (see page 216, for example). Had to throw this in. :smile:

is indicative of the external existence of objects — javra

Yes, and that's part of what makes this so fascinating and frustrating, we have indications of the existence of external objects, and plainly we take them as a given in our "vulgar reasoning", but we can't find proof for something that should be so obvious. So, it isn't as obvious as we think it is.

It's very hard for me to sustain his though experiment, that once we stop perceiving an object, we don't have many good reasons (although something must be there, in the world) to suppose it continues to exist. For as he says (I know I'm re-quoting him, but, he articulates it so well):

"...we find ourselves somewhat at a loss, and are involv’d in a kind of contradiction. In order to free ourselves from this difficulty... by supposing that these interrupted perceptions are connected by a real existence, of which we are insensible."

Italics mine.

Still, what I’ve read about Hume is often quite different than what I gathered from directly reading Hume. For one example, to me, Kant borrowed from Hume rather than debunking him. — javra

I think so too on Kant. He improved some of the framework, but did not solve the problems Hume raised. They're too difficult, in my opinion. You are a good reader, had I not read Strawson's work before Hume himself, I might have gotten the impression that causality is just constant conjunction, I can't be sure. But it is very, very clear, that Hume was what is now called a "mysterian", which should be the common- sense view that we are natural creatures, and hence some things are beyond our capacities, as some things are beyond the capacities of dogs or birds.

It's very hard for me to sustain his though experiment, that once we stop perceiving an object, we don't have many good reasons (although something must be there, in the world) to suppose it continues to exist. For as he says (I know I'm re-quoting him, but, he articulates it so well): — Manuel

But it is very, very clear, that Hume was what is now called a "mysterian", which should be the common- sense view that we are natural creatures, and hence some things are beyond our capacities, as some things are beyond the capacities of dogs or birds. — Manuel

For whatever reason, his allusions to instincts always resonated with me and quenched the otherwise potential difficulty in not having conscious reasons for an external world. Myself, I can fall back to the notion of the moon being there when no one is looking precisely on grounds of causal reasoning (riptides and such), and believe this can be extended to all external objects. But yes, Hume presented more problems than he resolved.

As to the title of "mysterian," I agree. From what I recall, maybe most notably, he was a kind of mysterian compatibalist who upheld both metaphysical free will and causal determinacy co-occurring; a very different species of compatibalism than what we have today wherein the notion of "freedom" is modified in any number of ways so as to suit a fixed stance on causal determinism (determinism being a term that wasn't coined yet in his day).

we have indications of the existence of external objects, — Manuel

Do we?

I think it is true that, broadly, we take beliefs, our individual beliefs and the beliefs of others, as indicative of how things are, but we know that we cannot deduce P from anyone's belief that P. We can take a middle course and count the beliefs of others as evidence, but such a procedure is rarely available when considering your own beliefs. There are very specific circumstances where that's reasonable, but in general there's something illicit in counting your own beliefs as evidence of their truth.

What Hume says quite definitely is that we do embrace the principle of the existence of body. Can we count that as evidence of the truth of this principle? Hume presents arguments that the principle cannot be supported either by our senses or by reason. Does that mean he leaves open the possibility of an 'argument from instinct' or some such thing?

He says that:

"The imagination tells us, that our resembIing perceptions have a continu’d and uninterrupted existence, and are not annihilated by their absence. Reflection tells us, that even our resembling perceptions are interrupted in their existence, and different from each other. The contradiction betwixt these opinions we elude by a new fiction, which is conformable to the hypotheses both of reflection and fancy, by ascribing these contrary qualities to different existences; the interruption to perceptions, and the continuance to objects."

Nature is obstinate, and will not quit the field, however strongly attack’d by reason ; and at
the same time reason is so clear in the point, that there is no possibility of disguising her, Not being able to reconcile these two enemies, we endeavour to set ourselves at ease as much as possible, by succesively granting’ to each whatever it demands, and by feigning a double existence, where each may find something, that has, all the conditions, it desires." (p.215)

He ends this section pretty much in a skeptical crisis, or close to it. The only thing I can read into all his very penetrating critiques that could offer a way out, is the highlighted portions I show above. We grant to each what it desires (nature and reason), but it is something we do,we don't have a choice. That pretty much sounds like an instinct to me, you can also look at javra's posts, which he has been nice enough to quote some of Hume's comments on instinct.

I am starting to realize that, even though one could read this chapter in isolation, it is by going to other parts of Hume's work, that one could find potential, reliefs as solutions seem to be wanting.

I think towards the end of this thread, I'll post here the Appendix, and only focus on like 2 pages, literally, that shows that he is not satisfied with his system, I think it shows that this problem is a bit too hard for us to solve.

Not what I intended at all. I was, I thought, following Hume's usage in using the word 'perception' to cover both impressions and ideas; so a perception is something present to the mind, of whatever source, a perceiving that is done 'by the mind's eye' we might say. — Srap Tasmaner

OK, my mistake then, but I tend to think that "perceive" and "perception" are most often used to refer to what the mind apprehends through the medium of sensation. When the mind creates something which is not the result of sensation we normally would use "imagination", or even "conception".

As I watch the birds flitting about in my front yard, I have an impression of a bird first here, then there, then there, as it moves from tree to tree. On a naive view, we might say there is a body, some force is applied to that body, and thus the body is caused to move through the air. We can see in the bird's flight inertia, which carries it along a certain path (modified by gravity and drag) until it flaps its wings again, adding a new vector which modifies its course, and so on.

Now consider me watching this: I have an impression of the bird; that impression is replaced by a different one with the bird elsewhere. Did my impression of the bird move? Of course not; I'm sitting on my porch and all my impressions of the bird are in the same place. Did my impression of the bird acquire an inertial force carrying it from one place to another? Perforce, no: my impression did not move; my impression had no such force applied to it. — Srap Tasmaner

I don't think this is quite right. What Hume seems to be asking, on behave of the skeptic, is why do you believe that you have an impression of a distinct and continuous object which you call "the bird" in the first place. You seem to have a continuous visual image, but it is full of motion and change, so why do you believe that there is a continuous, distinct object as part of that changing scenario, which is the bird?

All the following ideas, inertia and Newton's laws follow from this idea, that there are objects which have continued and distinct existence. We take it for granted that there are such objects, bodies, like the bird, because it appears like we have no choice in the matter. But if we have no choice in this matter, then there must be a cause of us taking this for granted. And if there is a cause of us taking the continued and distinct existence of objects for granted, we ought to be able to determine that cause.

So he proceeds to show that the cause is not sensation, or the senses. The reason why we believe in the continued and distinct existence of objects is not because that is the way sensation presents the world to us. Now we might be led toward something in the mind, like imagination, as the source of this belief in continued and distinct existence, but we still need to determine what causes us to have this idea.

We grant to each what it desires (nature and reason), but it is something we do,we don't have a choice. — Manuel

This is the key issue, saying "we don't have a choice". If we do not have a choice, then this is determined by fate or something, so there must be a cause of this belief. Where is that cause? It's not from sense nor from reason. Furthermore, the skeptic says that we do have a choice in this matter, and even that our belief in such objects is unfounded and therefore a bad choice. So skepticism affords us the capacity to believe what you say we have no choice but not to believe. And to validate this statement "we don't have a choice", we need to determine the cause which produces this as a necessary effect.

the skeptic says that we do have a choice in this matter, and even that our belief in such objects is unfounded and therefore a bad choice. — Metaphysician Undercover

As far as I can see, he doesn't present it a choice, postulating an enduring object is kind of like breathing or perceiving. It's not that it's a bad choice, as he says, (and pardon my over-repetition of quotes, but I think they matter):

"tis in vain to ask, Whether there be body or not? That is a point which we must take for granted in all our reasonings."

The issue is that the reasons the (mitigated) skeptic (he's no Pyrrhonian) teases out, turn out to be much weaker than what we would like, particularly when we look at the world through "common sense" - what he calls "the vulgar system".

So skepticism affords us the capacity to believe what you say we have no choice but not to believe. And to validate this statement "we don't have a choice", we need to determine the cause which produces this as a necessary effect. — Metaphysician Undercover

I think that for this, I'll need to introduce the Appendix to the Treatise, there he admits of his failure to provide what you ask for, it's very interesting and also very short, the relevant pages are like 2 at most.

Reading between the lines, it seems to me an inscrutable fact about how we experience the world. We strongly believe in the continuity of objects, but they change all the time. As do our perceptions.

We postulate a continuity we are not sensitive of, and hand wave it away by ignoring that each perception is new, and that in the intervals between experiences of the object it continues to exist as we perceived it, which creates the famous two-objects argument.

So, I see where you are coming from, and it is a very sensible question. But textually, I see no easy answer. In my own opinion, putting Hume aside, it's not evident what this necessary effect would be.

Reading between the lines, it seems to me an inscrutable fact about how we experience the world. We strongly believe in the continuity of objects, but they change all the time. As do our perceptions. — Manuel

The problem though, is that "continuity of objects", and "they change all the time", is inherently self-contradictory. So the proposition that "we strongly believe" in this, cannot be properly supported. If an object has continuous existence, it must continue to be the object which it is, or it becomes something else. That's what change does, it annihilates the object as being what it was, to be something else. So change negates the continuity of an object, by always making it something other than it was.

Hume's mistake in the outset, is to class "continued" and "distinct" together, and try to analyze them as both the same type of property. There is a fundamental inconsistency between "continuous" and "discrete", which makes classing these two together impossible. So his analysis of sensation is a bit off, because he presumes sense perceptions to exist as individual occurrences, rather than as a continuous experience. Since we continually sense through a duration of time, the perception itself is actually changing. Each and every sense perception occurs over a duration of time, so it contains change within it. Then if we try to break up a continuous perception into distinct perceptions we can never remove the activity from the sense perception. Notice page 192, where Hume attributes motion to sensation.

So what Hume refers to as a "single" or "distinct" perception cannot really be applied logically to sense perception, because the single perception would involve activity, hence an object being in more than one place at the same time. That is because motion, and the continuity of activity inhere within sensation. Therefore, there is a logical inconsistency between Hume's "single", or "distinct" perception, and a true description of sense perception. The true description would say that sense perception consists of a duration of time, and each act of sensation could logically be broken down into a multitude of distinct frames. This implies that the double existence, and resemblance relation referred to, is already inherent within any supposed "single" sense perception itself.

In reality, what we ought to conclude from this, is that there is an incompatibility between "continued existence" (what the senses provide us with the appearance of), and "distinct existence", (what reason tells us that a sense perception must consists of). While sensation provides us with a continuity of activity, without a division, or individualization of distinct parts, or objects, reason wants to break this down into individualized parts, or distinct parts, for comparison, and analysis of different rates of change occurring to the different objects within the continuous sense perception.

So the idea of distinct objects is assumed by Hume to be derived from imagination. And, when we take this idea of distinct objects, and apply it toward our sense perceptions, sensations, we assign to the sensations, objects with a continued existence, to match up with, or to be consistent with, the "continued existence" which sensation gives us.

He describes the role of memory in this imaginary creation of an object at 196. When the sound of the door is so similar to his past experience of the sound of the door, that it could not be anything else other than the sound of the door, he concludes that it would be contradiction to say it is not the sound of the door. Therefore, he has created in his imagination, an object, "the door", and the object thus entitled must have continued existence, to account for numerous appearances.

However, in criticism of Hume, notice that the claim of an object is dependent on something else, it's dependent on the memory, and this dependence makes the assumption of a "distinct" object imaginary, created by the mind to account for the similarity between instances of memory. That the object is "distinct" is fictional, imaginary, because that claim is a product of a need to account for similarity in instances of memory. Therefore, that the object is continuous is supported logically, but that the object is distinct is not. This is the consequence of him trying to make the assumption of "object" (as a distinct individual) consistent with sense perception which is continuous. The object loses its status of being a real distinct individual, because it requires the dual status, of two separate instances, and memory to relate them. And the separate instances are similar rather than the same.

At this point, p199, he proceeds to replace "distinct" with "coherent", such that the defining features of an "object" would be "continuous and coherent", and he says that "distinct" might be assigned later, perhaps as an after thought. The use of "coherent" instead of "distinct" allows for changes to the object between one appearance to the mind, and another, so long as the changes can be reasonably accounted for as coherent. Otherwise, each appearance of the supposed object, to the mind, would be distinct from any other, due to accidental differences. And then we'd have to say that these were distinct objects.

But textually, I see no easy answer. In my own opinion, putting Hume aside, it's not evident what this necessary effect would be. — Manuel

The "necessary effect" is the assumption itself, the assumption of a body, or an object. If we have no choice in this matter, as Hume says, then this assumption must be taken as necessary. Whatever is necessary must be caused, as the effect of that cause. Therefore there must be a cause which necessitates this effect (the assumption of bodies and objects) giving it the status of necessary.

If an object has continuous existence, it must continue to be the object which it is, or it becomes something else. That's what change does, it annihilates the object as being what it was, to be something else. — Metaphysician Undercover

I don't see how this follows. I mean, one can use the example of the Ship of Thesus: we replace one part of the boat with new wood and discard the old parts, it's literally not the same object - as it has new pieces in it, but we still recognize it as the same ship.

Likewise, if we are looking at a flower, miniscule parts of the flower are blown off by the wind, so it's literally not the exact same object one moment to the next, but we still recognize it as the same object. You can think of it as flower at T1 and flower at T2.

Therefore, that the object is continuous is supported logically, but that the object is distinct is not. This is the consequence of him trying to make the assumption of "object" (as a distinct individual) consistent with sense perception which is continuous. The object loses its status of being a real distinct individual, because it requires the dual status, of two separate instances, and memory to relate them. And the separate instances are similar rather than the same. — Metaphysician Undercover

There is this difficulty, of thinking about distinct existences, I agree. Nevertheless, it looks to me as if there is something about a given object that makes us recognize it as that specific object, otherwise, it seems to me that we would have no way to distinguish on object from another. But it is problematic, no problem granting that.

The "necessary effect" is the assumption itself, the assumption of a body, or an object. If we have no choice in this matter, as Hume says, then this assumption must be taken as necessary. — Metaphysician Undercover

But we have cases, which aren't that rare, in which we imagine objects to exist, when they do not: mirages, dreams, hallucinations, mistaken perceptions and so on. So an object is not, strictly speaking necessary, even if in most of the cases of perception, this is what we assume to be the case.

There is an issue around the individuation of perceptions.

There's that passage where Hume claims perceptions are exactly what they appear to consciousness as, etc etc, so he's basically claiming they are self-individuating.

* Here it is, p. 190

For since all actions and sensations of the mind are known to us by consciousness, they must necessarily appear in every particular what they are, and be what they appear.

It's easy to pass over that bit as just the usual empiricist sense-data talk, but without it he has no basis for claiming that our perceptions are interrupted.

I don't see how this follows. I mean, one can use the example of the Ship of Thesus: we replace on part of the boat with new wood and discard the old parts, it's literally not the same object - as it has new pieces in it, but we still recognize it as the same ship.

Likewise, if we are looking at a flower, miniscule parts of the flower are blown off by the wind, so it's literally not the exact same object one moment to the next, but we still recognize it as the same object. You can think of it as flower at T1 and flower at T2. — Manuel

Well, The Ship of Theseus is usually presented as an example of how complex and difficult the subject of identity really is, not as evidence that identity is something simple as you seem to imply here. However, I would agree with you, that the law of identity allows that a thing might remain 'the same as itself' despite undergoing many changes, thus maintaining its identity as the thing which it is despite changing. But this idea of identity presents us with a stack of logical problems.

First, we would not be able to associate identity with any type of description of the thing, because we are wanting to say that the thing remains the same thing and continues to be the same thing, despite changing and therefore requiring a different description. Furthermore, we would not be able to associate identity with any type of determination as to "what" the thing is, meaning a specified type of thing. This is because by allowing that a thing can change, and still maintain its identity by always being the same as itself, we'd have to allow that the thing could even change type, and still remain its status as the same thing. And even if we tried to establish a boundary between types, and tried to enforce a rule whereby the thing if it crossed that boundary would stop being itself, the thing that it was, to become something different, a new thing, then we'd need some principle to create this boundary. And what sense would it make to say that the thing stopped being itself, to become something different from itself.

To get back to the text, we need to pay close attention to what Hume says about "identtiy" from page 200 onward. Hume does not interpret the law of identity in the same way that you and I do. We accept that a thing changes yet continues to be itself, thus the same thing that it was, thereby maintaining its identity despite changing. Hume thinks that a thing must remain exactly the same, perfectly unchanged, to maintain its identity, by the law of identity. He attributes "identity" to invariableness:

We cannot, in any propriety of speech, say,
that an object is the same with itself, unless we mean, that
the object existent at one time is the same with itself existent
at another. By this means we make a. difference, betwixt
the idea meant by the word, object, and that meant by ifself
without going the length of number, and at the same time
without restraining ourselves to a strict and absolute unity. — p201

So you see he interprets the law of identity in a way completely different from you and I by associating "identity" with invariableness, remaining unchanged. Furthermore, this must have a profound effect on how he understands continued existence. If, to have continued existence, and maintain its identity as the thing which it is, a thing must remain unchanged from one time to another time. This is completely different from how you and I understand continued existence, which presumes that a thing continues to be the thing which it is, despite changing.

There is an issue around the individuation of perceptions.

There's that passage where Hume claims perceptions are exactly what they appear to consciousness as, etc etc, so he's basically claiming they are self-individuating. — Srap Tasmaner

The problem I have with this, is that I do not see the basis for claiming that individuation is something carried out by the senses, therefore inherent within the sense perception, rather than something produced by the mind which is apprehending the sensations. The problem again is in the ambiguity of "perception". If "perception" refers to what is created by the mind, then there is no need for any sense input, like what Manuel describes above. But when we say "sense perception", then a necessity for sense input is implied. However, in the case of sense perception, the part which is created by the mind is not distinguished from the part input by the senses. So even if we say perceptions are self-individuating we don't know for sure how much of this is done by the senses, and how much is done by the mind. So we still do not get at the source of individuation

So we still do not get at the source of individuation — Metaphysician Undercover

But Hume explicitly doesn't care.

Same page is where he says all these mental phenomena (perceptions, feelings, ideas, what have you) are 'on the same footing.' And he assumes they are presented to the mind as discrete, already individuated packets.

He is absolutely *not* going to say they are shaped by the mind, because that suggests there is something to be shaped, something that already has a distinct existence outside the mind. But he explicitly wants only to look at perceptions etc. insofar as they are dependent on the mind: for Hume they exist at the moment we are conscious of them, and that's it.

Yeah, this will be interesting to discuss, I'll get back to you sometime tomorrow, there's a lot to say here.

Here's another way: there can be, I think Hume thinks, nothing in the perception itself that would tip off the mind as to its origin or nature. Thus we have no surefire way of distinguishing veridical observations from hallucinations or dreams or optical illusions. Hume accepts the usual argument as a step toward considering perceptions only, however they appear to the mind.

But Hume explicitly doesn't care.

Same page is where he says all these mental phenomena (perceptions, feelings, ideas, what have you) are 'on the same footing.' And he assumes they are presented to the mind as discrete, already individuated packets.

He is absolutely *not* going to say they are shaped by the mind, because that suggests there is something to be shaped, something that already has a distinct existence outside the mind. But he explicitly wants only to look at perceptions etc. insofar as they are dependent on the mind: for Hume they exist at the moment we are conscious of them, and that's it. — Srap Tasmaner

Actually things are the opposite of what you say here, he explicitly does care about this matter. He is asking about "distinct existence", and this requires that the individual, the person or self, is separated from the rest of the world. It's a sort of inverse way of looking at things, but this is why he mentions the subject of personal identity. Then he explicitly concludes that the senses themselves cannot produce this separation. The senses don't distinguish what is part of yourself, and what is not.

So we cannot say that he assumes that the senses provide discrete individuated packages. He actually seems to say the exact opposite, that the senses cannot perform such a feat of individuation. This is why the senses cannot produce a dual existence.

It may be the case that he believes that perceptions exist only at the moment we are conscious of them, but he has very clearly stated that he is interested in causation, and this implies what is prior to that moment. His enquiry is into the causes of our belief in the existence of body:

The subject, then, of our present enquiry is concerning
the causes which induce us to believe in the existence of
body

If he does not separate that which is derived from the senses from that which is created by the mind, he is left with the appearance of one cause, rather than "causes".

Hume accepts the usual argument as a step toward considering perceptions only, however they appear to the mind — Srap Tasmaner

I think you are hiding behind the ambiguity of "perception". Haven't you already said that "perception" includes all things apparent to the mind. So a belief must be a perception, and he has distinctly stated that he is enquiring into the causes of a particular belief, therefore a particular perception. So he cannot be considering perceptions only, because this would imply an infinite regress or circular reasoning, where only perceptions cause other perceptions. Rather, he is considering the causes of perceptions. In the enquiry concerning the causes of what appears to the mind, we have to have some way to get outside "what appears to the mind", or else what appears to the mind is caused by the mind itself, and all reality becomes hallucinations and dreams.

So we take the existence of "body" for granted, as something outside the mind, and we say that it has causal effect within the mind. But if we did not assign causation to body, then we are just left with the mind doing all the causing, hence creating the illusion of "body", and we would still be in the same place, unable to justify the existence of anything outside the mind. So, we must determine that body has real causal efficacy to escape the skeptic's trap. Though it is true that only perceptions, within the mind, appear to the mind, it is also true that through the concept of "causation", we might be able to conclude the existence of something outside the mind. This would get us past skepticism.

Yeah, this will be interesting to discuss, I'll get back to you sometime tomorrow, there's a lot to say here. — Manuel

Here are what I consider the key points. First, the "broken perceptions". Sensation is often interrupted, (for whatever reason is unimportant), so that we sense the environment at one time, and then again at a later time. Through memory we compare, and observe "resemblance". But resemblance is not the same as "perfect identity", and this inclines us to believe that the object of the past impression was annihilated and replaced by a new object. Therefore, the principal task for justifying the continued existence of an object is to establish consistency between "resemblance" and "identity", what he refers to under "Secondly" at the beginning of page 200.

Ok, now I can reply. There are many aspects one can choose to focus on in this chapter, so it can be interpreted in several ways, I want to single out a brief passage, prior to you quote of "We cannot in any property of speech...", he speaks about how time implies succession, and then says that:

"This fiction of the imagination almost universally takes place; and ’tis by means of it, that a single object, plac’d before us, and survey’d for any time without our discovering in it any interruption or variation, is able to give us a notion of identity." (pp.200-201)

I think it is important to point out, that in Hume's use of the term, "fiction", does not mean what we mean by it today, something not being "real", or belonging to mythical tale or a novel. It simply means "more than is warranted by the empirically available evidence." It is real, in the sense that we do experience the identity of objects, but when we look at the evidence, it turns out to be weaker than we would like.

He says, on p.203:

"When we fix our thought on any object, and suppose it to continue the same for some time; 'tis evident
we suppose the change to lie only in the time, and never exert ourselves to produce any new image or idea of the object. "

That speaks of your concerns that each perception is different, and it is by resemblance that we posit continuity. True. Now he says, on p. 204:

"I survey the furniture of my chamber; I shut my eyes, and afterwards open them; and find the new perceptions to resemble perfectly those, which formerly struck my senses. This resemblance is observ’d in a thousand instances, and naturally connects together our ideas of these interrupted perceptions
by the strongest relation and conveys the mind with an easy transition from one to another. "

Italics mine. Each perception is new, and he does not want to distinguish between objects and perceptions. Yet he still speaks of "my chamber", if he didn't have a notion of identity, he couldn't speak like this, because he would have no way to separate his chamber from anything else.

An important, passage, I think, is this:

"We may begin with observing, that the difficulty in the present case is not concerning the matter of fact, or whether the mind forms such a conclusion concerning the continu'd existence of its perceptions, but only concerning the manner in which the conclusion is forrn'd, and principies from which it is deriv'd."(p.206)

Italics and bold mine. So, I don't think there is a tension is speaking about identity as we do, in regard to the The Ship of Theseus, only that Hume goes deeper and presents us with problems that go beyond, or are deeper in a sense, than the example of the ship.

As I said, one can pick out many quotes here, supporting different views, so one should keep this in mind. What I quoted here is what I think makes sense from a holistic perspective, but this can be debated.

As to those impressions, which arise from the senses, their ultimate cause is, in my opinion, perfectly inexplicable by human reason, and 'twill always be impossible to decide with certainty, whether they arise immediately from the object, or are produc'd by the creative power of the mind, or are deriv'd from the author of our being. — Part III, Section V, p. 84

my chamber — Manuel

Indeed. It's why I was thinking we'd need to graph out the arguments, because they are sometimes presented in terms that other arguments will undermine.

I haven't spotted a similarly straightforward example in the Treatise, but there's this in the Enquiry:

This table ... preserves its existence uniform and entire, independent of the situation of intelligent beings, who perceive or contemplate it.

But this universal and primary opinion of all men is soon destroyed by the slightest philosophy, which teaches us, that nothing can ever be present to the mind but an image or perception, and that the senses are only the inlets, through which these images are conveyed, without being able to produce any immediate intercourse between the mind and the object. The table, which we see, seems to diminish, as we remove farther from it: but the real table, which exists independent of us, suffers no alteration: it was, therefore, nothing but its image, which was present to the mind. — Section XII, Part I

How does this argument work? Hume demonstrates that only perceptions are present to the mind, not objects, by showing that perceptions change when objects don't; but then he will later use the fact that only perceptions are present to the mind to argue that the hypothesis of double existence is insupportable, that we have no grounds for a belief in an object separate from our perceptions as their cause. — But then where does that leave this argument which originally established that only perceptions not objects are present to the mind? If we can't contrast the apparent extension of the table with its 'real' extension, then we have no argument at all. We have something vaguely of the form P → Q → ~P. Yikes.

And it happens all over the place, his description of his chamber being another example, and his simple reliance on his own identity.

Then he explicitly concludes that the senses themselves cannot produce this separation. The senses don't distinguish what is part of yourself, and what is not. — Metaphysician Undercover

Hume was not an idiot. He was certainly aware of sensory boundaries such that when one hits the nail into the wall with the hammer, it does not hurt whereas when one hits the fingernail, it does. Or that one can see and move ones hand, whereas one can see, but not move another's hand. What he was arguing against was the Cartesian theorised absolute self, devoid of, ie prior to, sensation and perception. Descartes constructs his doubt of the senses so as to produce an immaterial mind. Hume by contrast says that this doubt is in fact impossible, and is a fabrication of philosophers. The mind goes beyond the senses to 'make sense' of them in ways that reason cannot justify, but simply has to accept. There is no proof of existence of anything, self or world, but what is evident needs no proof.

For as to the notion of external existence, when taken for something specifically different from our perceptions, we have already shewn its absurdity. — Hume

P188.

This makes Hume a direct realist, in contrast to Kant, who puts back a separate external existence as the unfathomable, (and to Hume, absurd) Noumenon.

The subject, then, of our present enquiry is concerning the causes which induce us to believe in the existence of body : And my reasonings on this head I shall begin with a distinction, which at first sight may seem superfluous, but which will contribute very much to the perfect understanding of what follows. We ought to examine apart those two questions, which are commonly confounded together, vizi. Why we attribute a CONTINU’D existence to objects, even when they are not present to the senses ; and why we - suppose them to have an existence DISTINCT from the mind and perception.

The search is for a ground, a bedrock for knowledge. For Descartes, reason, for Hume, perception. Thus he (Hume) looks for causes of belief not reasons for belief. And as we know from elsewhere, he also argues that causes are unfounded ideas, that arise from but are not present in perception, along with continued existence and distinct existence.

We have something vaguely of the form P → Q → ~P. Yikes.

And it happens all over the place, his description of his chamber being another example, and his simple reliance on his own identity. — Srap Tasmaner

Just so. Because he is arguing against rationalism. Rationalism is the belief that one can reason from first principles to the world. Descartes shut himself in a darkened room and tried to argue his way out of it. Hume says you cannot argue your way out of a paper bag, but fortunately you don't have to, because the world is already present and available to be made sense of.

Hume says you cannot argue your way out of a paper bag, but fortunately you don't have to, because the world is already present and available to be made sense of. — unenlightened

Except it's not a world of objects but of perceptions; objects are mere prejudice. Empiricism slides into idealism.

That first quote you gave of Hume is indeed beautiful and I think, spot on. I didn't post it because I don't want to hammer home the "mysterian" angle, but it's there in the text.

But then where does that leave this argument which originally established that only perceptions not objects are present to the mind? If we can't contrast the apparent extension of the table with its 'real' extension, then we have no argument at all. — Srap Tasmaner

Yes, I agree that this is quite a problem for him, because if objects and perceptions were identical in all respects, there would be no way to distinguish the table or chamber because each perception is new and then what reference point would we have between my perception of the table at t1 and my perception of the table at t2?

One wouldn't even be able at t2, to call our perception "a table" at t1, it's a new object. We have to postulate a temporal space (a second, fractions of a second?) to t1 so a resemblance can arise which relates it at t2.

I think a key passage to make this less confusing is when he says:

"The only conclusion we can draw from the existence of one thing to that of another, is by means of the relation of cause and effect, which shews, that there is a connexion betwixt them, and that the existence of one is dependent on that of the other, The idea of this relation is deriv’d from past experience, by which we find, that two beings are constantly conjoin’d together, and are always present at once to the mind." (Italics mine) (p.212)

But then he goes on to say: "But as no beings are ever present to the mind but perceptions; it follows that we may observe a conjunction or a relation of cause and effect between different perceptions, but can never observe. it between perceptions and objects." (p.212)

I think this last quote is problematic, a stimulus is needed.

To end this post, he does say:

"There is a great difference betwixt such opinions as we form after a calm and profound reflection, and such as we embrace by a kind of instinct or natural impulse, on account of their suitableness and conformity to the mind." (p.214) (again, italics mine).

So clearly a "natural impulse" is quite important in our ordinary image of the world.