Insofar that scientific description is taken as a basis for ontology: Why not make the claim that the photon demonstrates that we don't need mass for something ot be physical?

energy are massless (not physical) eg a photon, — Benj96

:roll:

Photons are physical. Energy is physical action. And phenomonology pertains only to organic subjectivity, not to "not physical photons".

:up:

In this way, other potnetially immaterial things like minds can exist even if they have no directly physical/tangible basis, they can be metaphysical properties that lead to actionable consequences (behaviours) via their interaction with material existants. — Benj96

So then do the metaphysical properties we attribute to minds arise from the interface between our subjective thoughts and the material reality we perceive and interact with, or do minds have the properties we might predicate to them merely because we observe how they interact with material existents (behaviors)? I ask this because if it were just the latter that made minds what they are there would be no subjective anchoring to help determine the specific properties of any minds. To make it quite literal, ascertaining some properties would be like trying to determine someone's political beliefs with a multitude of simple puzzle boxes. So, I think that to make sense of what it means for a mind to exist in terms of descriptive properties you would need to account for some subjectivity; furthermore, I think it is not that useful to try to boil it down just to interactions with material existents in the form of behaviors because subjective beliefs or qualities, which don't necessarily act in themselves, play a gigantic part in determining how one forms intentions and acts.

For me, an existent is something that "acts". — Benj96

I think that is still too narrow a definition. For me, an existent is that which is not nothing. This might include particular things like a particular triangle that exists in a space without time and therefore cannot act, or general things (properties) like a general triangle or a general mind or number 2, which cannot act either. Plato thought that general things are more real than particular things. There are also relations, which some philosophers think are more real than things (non-relations).

Some of my thoughts on existence:

A thing comes into existence from non-existence at a certain point in time and returns to non-existence at another future point in time. This non-existent state is not a state of nothingness but a state of perfect symmetry. When this symmetry is broken, the effect is the manifestation of spatial dimensions and things in those dimensions in the form of fundamental particles. Each particle represents a quantum of imbalance (imbalance meaning separation from 0, or broken symmetry) in the universe. The measure of broken symmetry determines its rest energy. This rest energy is what allows for the persistence of its existence, and when this rest energy is resolved by the restoration of its broken symmetry through fusion with its antiparticle, existence for both particles ceases.

It's interesting to note that virtual particles are considered to not be real because they last such a short time, and so it appears that for a virtual particle to become real, it must persist longer than 1 or 2 Planck moments. One Planck moment for the manifestation of two particle pairs and one Planck moment later for annihilation. Such a short existence precludes it from effectively interacting with anything else, except sometimes they do and get to become real particles for arbitrarily longer amounts of time.

The long-term effect of these lingering real particles is that they increase the chance (skewed probabilities) of other virtual particles becoming real more and more. The result is the first semi-stable reality composed of existent fundamental particles. Emergent forms of existence continue on from this point forward with an established arrow of time.

Some interesting questions to think about:
What exists such that it allows for the potential or possibility of existence or existing things?
Does it make sense to state that the ground of existence itself exists?
Is there an even more fundamental concept than existence?
What are the requirements for existence to be possible?
Is existence its own requirement; does the ground of existence stand on its own ground?

In this way, it does not need to be a material/physical thing, it only requires a phenomenology. For example some forms of energy are massless (not physical) eg a photon, but still acts - has the ability to do work. — Benj96

This is confused. Energy and mass aren't existents (per se), they are properties of things that exist, and they can be converted to each other (that's entailed by E=MC^2).

As far as I can tell, everything that exists has properties; properties (including energy and mass) don't exist independently of the things that have those properties.

For me, an existent is something that "acts". — Benj96

Hence existents are said to be actual.

Energy and mass aren't existents (per se), they are properties of things that exist, and they can be converted to each other (that's entailed by E=MC^2). — Relativist

:100:

That which possesses a quality that sufficiently distinguishes itself from its surroundings or environment in an observable way; that which is distinct. Fair enough, is that not?

To be is to be the value of a (bound) variable remains a favourite.

So to exist is to be the sort of thing that can be slotted into the expression "something is f". Grass exists because it satisfies "Something is green". The cat exists becasue it satisfies "Something is on the mat".

Benj's "something exists if it acts" works in a limited way becasue to act is to lie within the scope of a predicate. It amounts to a restricted version of Quine's chestnut.

This is not to say there are no issues remaining. The main one here is convincing folk that "exist", "real" and "physical" are not synonyms.

Nice.

Yep.

Much the same.

Kripke had other ideas, of course. All good fun.

(Apologies for the edit - poor expression and poor memory. )
(And a second edit, becasue the point needed bolding. But it will not be regarded, and folk will continue arguing about whether energy exists for page after page...)

This is not to say there are no issues remaining. The main one here is convincing folk that "exits", "real" and "physical" are not synonyms. — Banno

Exactly this. Unicorns exist but they are not real. They exist as concepts (especially in fairy tales and they act too, fictionally speaking).

My definition of existence is anything that has being either in fiction or reality (physical world)

Yep, more or less. After that we just have to explain what to do with the present King of France.

This is confused. Energy and mass aren't existents (per se), they are properties of things that exist, and they can be converted to each other (that's entailed by E=MC^2). — Relativist

But matter (mass) is an existent of itself is it not ? Matter is mass as mass is a physical characteristic and exists in itself and can be used interchangeably to refer to matter (matter=mass=energy) so it is not a property of matter rather it is its own existent. The total mass of the universe for example is not a property of any one thing.

But matter (mass) is an existent of itself is it not ? — kindred

By writing "matter(mass)" are you suggesting matter and mass are identical? They're not.

Mass is a property that most things have, although photons are things that have 0 mass.

The original question is a fundamental question in ontology: what exists? Personally, I lean toward physicalism, which entails the premise that only physical objects exist. I don't believe properties are objects. Rather, a property is a way the object is. If I'm wrong, and properties are objects- it would have to be explained how a property is somehow attached to an object, and also explain where properties reside when they aren't associated with an object.

Physicalism could be false. Perhaps there are immaterial objects like angels and demons. I see no reason to think so, but you need to consider whether you want an ontology that treats them as, at least possible objects. If so, this means you need broader definition of "object".

Mass is a property that most things have, although photons are things that have 0 mass. — Relativist

Yes photons are confusing because they’re both waves and particles as far as i understand the concept.

By writing "matter(mass)" are you suggesting matter and mass are identical? They're not. — Relativist

I’d say that mass is not just a property but a thing in itself. My radio is just a lump of mass and not just a property of the radio. The problem appears to be linguistic here.

I’d say that mass is not just a property but a thing in itself. My radio is just a lump of mass and not just a property of the radio. The problem appears to be linguistic here. — kindred

Just a lump of mass? Suppose it has a mass of 500 grams. Is it the same as a 500 gram, lead fishing weight?

Yes photons are confusing because they’re both waves and particles as far as i understand the concept — kindred

All particles behave like waves under some circumstances. They're all quanta of quantum fields (according to quantum field theory).

Just a lump of mass? Suppose it has a mass of 500 grams. Is it the same as a 500 gram, lead fishing weight? — Relativist

Of course not they’re different objects with their own separate existence but they’re both just lumps of mass. Language here serves to differentiate between different objects.

Of course not they’re different objects with their own separate existence but they’re both just lumps of mass. Language here serves to differentiate between different objects. — kindred

Aren't there actual differences between objects, that would exist even if no one was around to use language?

Sure there would be differences. What’s your point ? Language is just used for naming and describing different things it does not necessarily follow that the objects being described are not lumps of mass.

My point is that I was discussing what exists, not what names we give things.

Existent/thing: in humans, that which is, or possibly is, an affect upon the senses.

I would define it as anything that has any value of any property specific to itself. (Having the property and the value be specific to itself, not have a unique property/value).
For example, a down quark is a thing because it has a charge (one of many properties), but it is not two things because all the properties of the quark are not properties of only one of two smaller things (according to our understanding).

Existent/thing: in humans, that which is, or possibly is, an affect upon the senses. — Mww

What about microscopic organisms which we can’t see with our naked eye but only through microscopes do they only exist when they’re perceived via such apparatus or independently of our perception ?

There are other things things that exist too which have no discernible affect upon our senses such as magnetism (a type of force which only affects magnetic material).

What about microscopic organisms…. — kindred

Fits the offered criterion of an existent/thing, no different in principle than an ice cube in a glass.

There are other things things that exist too which have no discernible affect upon our senses such as magnetism — kindred

Feynman says fields are things, but he’s a science guy having little truck with philosophers. With that in mind, an affect on the senses by an effect of a cause does not necessarily make the cause a thing. From a philosophical/epistemological perspective, I’d rather leave such phenomena as magnetism, gravity, charge, and whatnot, as forces or fields, and leave that which is acted upon by them, as existents/things.

But that’s just my opinion, in answering the question contained in the thread title.

After that we just have to explain what to do with the present King of France. — Banno

He doesn't exist because he's logically inconsistent. Same for the present unicorns on this planet.

What if you witnessed a unicorn in fiction such as in a movie or a book, does the unicorn exist in this type of frame or it doesn’t exist because it’s not real? Do existents always have to have a one to one correspondence with reality. Do triangles exist in your view ? They’re not mythical but abstractions of thought. If a unicorn exists in thought the same way a triangle does why can’t we say it doesn’t exist ?

What if you witnessed a unicorn in fiction such as in a movie or a book, does the unicorn exist in this type of frame or it doesn’t exist because it’s not real? — kindred

In such cases, a "unicorn" can exist as an image on the movie screen or as an encoding of that image on a tape or a digital device, or as a printed word ("unicorn") on a page in a book. It can also exist as a neurological object in your brain, or as a particular object in your mind (just in case your mind is not identical with your brain). It might also exist as a general object (universal) whose instances are particular objects in minds or neurological objects in brains or printed words on pages or images on movie screens.

Do existents always have to have a one to one correspondence with reality. — kindred

In the most general sense, reality is all that exists, and all that is not nothing exists. For practical purposes though the words "reality" and "exist" are often used in a narrower sense, for example for particular objects that exist outside our heads. Or not for "unicorn" in the senses I mentioned above.

Do triangles exist in your view ? They’re not mythical but abstractions of thought. — kindred

In my view every entity that is defined in a logically consistent way exists. An inconsistently defined entity is actually not an entity/something but nothing (an inconsistent definition has no referent). Triangles may exist as particular thoughts or as universals but also as particular objects drawn on a piece of paper, for example.

Existent/thing: in humans, that which is, or possibly is, an affect upon the senses. — Mww

A recipe for solipsism.

He doesn't exist because he's logically inconsistent. Same for the present unicorns on this planet. — litewave

There's nothing logically inconsistent about the present King of France, no contradiction that follows from the very idea.

It's just that there isn't one.

There's nothing logically inconsistent about the present King of France, no contradiction that follows from the very idea. — Banno

It would be logically inconsistent for an entity to exist at a place and time where it doesn't exist. The present king of France doesn't exist on our planet, therefore it would be logically inconsistent for him to exist on our planet.