This is that long post. The aim of it is to try and move towards the source of disagreement between forum direct realists (represented by
@jamalrob,
@unenlightened and I) and forum indirect realists (represented by
@Michael,
@Marchesk {maybe, now} and
@Isaac).
So it seems to me that the disagreement between direct and indirect realists is regarding the
type of relation between perception and the environmental object it regards, and the
properties of this relation. I think it is crucial to keep in mind that there can be more than one type of relation between a body and the objects in its environment.
The overall framework I'm going to adopt for this is one of active perception; roughly stated: active perception is an account of perception in which perception is goal oriented and part of every
perceptual feature is a proposed collection of
environmental interventions which are in accord with those goals. To put super special emphasis on this; the
goals and environmental interventions are part of perception, and our
perceptual features are laced with (summaries of) them. For those coming from a phenomenological perspective, the
goals and environmental interventions might fruitfully be thought of as Gibson's affordances or Heidegger's for-the-sake-of-which. For those coming from a more analytic perspective, such goals and environmental interventions may fruitfully be thought of as a kind of
theory-ladened-ness of perceptual features concerning theories of practical activity and environmental development given our interventions within it.
A key term there which I've not talked about is
perceptual feature. Roughly what that is is a salient element of
an instance of perception; an object under a viewpoint relative to a task in an environment, the shifting weight of a hammer prompting counterbalancing muscle contractions along the arm to ensure the nail is hit, the duck or the rabbit in the duckrabbit. Generally, they might fruitfully be thought of as a goal-oriented model or representation of something in the environment. In visual terms, they are like pictures insofar as they
represent environmental features, but they are unlike pictures insofar as they
promote and are part of activities; they are not just corpuscles of propositional content, they are saturated with
normatively informed expectations of environmental development
relative to our tasks.
In these terms then, the distinction between direct and indirect realism that I wrote for Michael and he approved of:
(Direct realism (content) ) The properties of perceptual content of a perceptual event are identical with those of what the perceptual event is directed towards.
(Indirect Realism (content) ) The properties of perceptual content of a perceptual event are not-identical with those of what the perceptual event is directed towards.
Can be recast to:
(Direct realism (feature) ) The properties of a
perceptual feature of a perceptual event are identical with those of what the perceptual event is directed towards.
(Indirect Realism (feature) ) The properties of a
perceptual feature of a perceptual event are not-identical with those of what the perceptual event is directed towards.
But notice that
perceptual content is construed as
merely descriptive; is the red of the perceptual feature I have of the apple the same as the colour properties of the apple? We would not be able to answer questions of identity and non-identity of properties regarding
all facets of the perceptual feature simply because there is no (to use Lockean terms) primary quality of the apple that could be identical to my desire to eat it.
There is, however, still the question of whether the
descriptive content of a perceptual feature is
identical with some primary quality of the apple. This doesn't make too much sense for the reasons
@jamalrob and
@Marchesk discussed:
I think jamalrob is arguing that how an object looks, tastes, feels only applies to perception. There's no such thing as what an object looks like without someone seeing it. The indirect realist goes wrong by assuming there is, and then proposing the additional mental intermediary. But there's no need for the intermediary if the act of seeing is what something looks like.
If that sort of argument works, then the debate is rendered moot. There's still a realist question of what objects are independent of perception, but they aren't like perception — Marchesk
But there are still relevant questions like; what qualities of the apple
promote the generation of the (descriptive component) of my perceptual features of it? And in that space of questions, it seems fine to talk about red and rods and cones and of a
relationship of representation/summary/codification between the perceptual features I have of the apple and of the apple's properties.
We can also talk about the argument from hallucination in those terms; specifically what is being short circuited or bracketed in asking the question is that the descriptive content of my perceptual features can be present (through some bodily process) without the
environmental and sensorimotor conditions that generate the perceptual feature
in normal circumstances. The argument seeks to change the conditions of environmental exposure (by removing them) without changing the descriptive component of what perceptual feature is being generated.
But notice first that that argument removes two vital components of
active perception;
Active accounts of perception
have exploratory and goal-directed environmental interventions as part of the
perception itself. In that regard, hallucinations, or the argument from dreaming, are effectively not forms
of perception because two necessary components of perception have been denied of it. Only the relation or absence of relation of descriptive content remains.
I think that the realists here would find the above paragraph
very cononsonant with their direct realist intuitions. But why? I think the intuitions that forum direct realists have regarding
directness regard the
character of relation between perceptual feature and what it regards. Recall that
environmental interventions really do change things in the environment; the underlying intuition is that our perceptual features
when including the exploratory/goal-oriented component are in direct
causal contact with the environment. Causal contact persists even while making representational/inferential mistakes; in any instance of perception our sensorimotor systems are in direct causal contact with the environment, be that contact more or less adequate for our purposes The inferential summary that our perceptual features
are leverage sensory and interventional exploration of our environment; eg moving one's head to change the field of view. Because of this, for the
causal covariance of a typical instance perception to be ensured, our sensorimotor systems must be in direct causal contact with the environment..
Specifically for Isaac: the interventions we enact are not causally separated from environmental hidden states, even if the inferential summary of environmental properties are. When there is a successful modelling relationship between a perceptual feature and what it regards; or an intervention and our overall model of the causal structure of our environment; the overall perceptual state we're in, and its perceptual features, are indeed
informative of our environmental objects. But
informational dependence in that sense is not the same thing as saying
the properties of the apple in total are existentially dependent upon our perceptions of it.
For indirect realists; the proof of indirectness is inferential representation.
For direct realists; the proof of directness is causal contact.
This is as expected; our perceptions are difference sensitive, and exploratory interventions make environmental and bodily differences to change the environment and the
generated inferential summary we have of it through the collage of our perceptual features in an event of perception.