The question of whether there are unconscious perceptions, and if so, their nature, has received considerable attention from philosophers and psychologists from the seventeenth century onwards. One's answer to this question will reveal a lot about one's conception of perception in particular and of the nature of the mind in general. Some care is needed in approaching the question. 'Perceive' is sometimes taken to mean 'be aware of', and if it is so taken, of course one cannot perceive anything unconciously, by definition. Such a definition doesn't, however, dispose of the question, for one can either stipulate that by 'perceive', one means to 'have a mental representation' (for now, let me just stipulate that a mental representation is an internal representation that enables one to have a sense-based perception: the nature and status of mental representations is a topic that deserves considerable attention in its own right): if one takes 'perceive' in this sense, then one can have both conscious and unconscious perceptions. On this picture, all perceptions are representations, some of which are conscious and some of which are not. (The question of why some perceptions make it to consciousness is another good one that merits further attention, but I bracket it here.) There are numerous examples of unconscious mental representations, I present just one. If one is driving along the road, thinking about the question of whether there are unconscious perceptions, one may not be consciously attending to the road, but, nevertheless, one continues to follow the road, and to adjust one's driving to the road, and even, if something appears suddenly on the road, one may respond to it, even though one's attention is not focused on the road. It seems to me that one plausible explanation of this phenomenon--not the only explanation, to be sure--is to posit unconscious representations of the road. This is the sort of everyday phenomenon that provides good reason, I think, to hold that it is possible to perceive something unconsciously.

Synesthesia is a phenomenon in which the activation of one sensory modality leads to experiences in a second sensory modality: one common form of synesthesia is the perception of letters or numbers as inherently colored. This phenomenon has, I think, received relatively little attention from philosophers--although there are related remarks scattered throughout Wittgenstein's 'later' writings--in part because after years of neglect by psychologists, it has only relatively recently begun to receive sustained attention from them. Consideration of the phenomenon may well offer insights into a range of questions in the philosophy of mind, including the philosophy of perception, such as: the relation between different sensory modalities; whether different sensory modalities represent the world differently; and even the nature of consciousness, insofar as one problem for accounts of consciousness is explaining the experience of sensible qualities--sometimes called 'qualia', for qualitative experiences, a topic that consideration of synesthesia might well illuminate.

The answer seems pretty clearly to be yes. Touch and hearing both convey information about dimension. Think, for example, about the fact that a sound can be above you, or in front, or two the side. Or think of how you could tell that object A is taller than object B, but object B is wider than object A just by using your sense of touch.

If you're interested, here's a link to a video about a remarkable Turkish painter, blind from birth but able to convey subtle information about perspective.



http://www.youtube.com/watch?v=L3AgO6H0H98

Interesting question! There are philosophers who would seek to undermine the whole picture of ourselves that is presupposed by your question. Some of them argue that we do make direct contact with the objects we touch, feel, smell, hear, and taste and that the idea that we only directly deal with sensations (or what is sometimes called "sense-data") is an illusion brought on by people like Descartes or, in the 20th century, by Bertrand Russell or A.J. Ayer. But I am inclined to think we do not directly feel and see what is around us; while I think we do (under normal circumstances) relaibly see and feel "what is really out there" this is mediated (in my view) by sensations, our visual field and so on. On this view, skepticism of an even very radical sort is conceivable. It is logically possible (I suggest) for the movie the Matrix to be right; we merely think we see what is really there, but we are being manipulated by complex computers to have the sensations we are having.

One other matter to consider: Your first question "What is reality?" has been at the heart of a great deal of philosophy historically. One of the important points that has been made is that when people worry whether they only face a world of appearance, they can at least be confident in the reality of appearances. Augustine used such reasoning in his reply to the skeptics of his day who seemed keen on doubting everything. Augustine countered that there are some things that cannot be doubted (the self, and appearances, among other things).

Certainly, one can consult a variety of methods of determining if today is Tuesday, and once one knows that, bingo, the problem is solved.

great question -- though it's not like there is 'an' answer here, though there is much to be debated as you formulate your own anwer. For one thing one must try to separate 'the 'experience from the language we use to speak about it and focuse on the experience. And anecdotal (incl medical) evidence seems to suggest it's no uncommon for people to report things, under anesthetics of various sorts, that they are having terrible pains but somehow don't mind them. That prima facie suggests that that very experience, the painful one, doesn't have to be a cause of pain, so to speak -- which suggests it is NOT inherent in pain to be avoided/disliked. (Lnguage complicates this b/c we might choose to use the word pain in that restrictive manner and thus claim those un-minded experiences do not earn the label 'pain' -- that's a semantic choice but it doesnt seem to effect the ontological conclusion.)

hope that is helpful ...

The positions and numbers of branches and leaves of trees and plants are governed by Fibonacci series: 1,1,2,3,5,8.13 . . . . , so there is order in their arrangement. Whether this pattern exists seems to have little or nothing to do with how used to it we are.

I'm not sure that whether something occurs "naturally" nor whether it's been thus for a long time is the issue here. Nature gives us many examples of things that are very orderly and not "chaotic" or "random" at all. Crystal structure is an obvious example. So is the periodic table. And things with human origins can display a lot of randomness. Spin a roulette wheel a bunch of times and try to predict the outcomes.

A bit too simply, there are cases -- old and new, natural and human-made -- where we can make very accurate predictions about what comes next, so to speak, on the basis of what's come before. And there are other cases where our predictions will be (so to speak) no better than tossing a coin. I think that's what lies behind the distinction you're making, and there are branches of science and mathematics that have lots to say about the matter. (One particularly relevant field is information theory.)

Of course, there can be hidden order where there is apparent chaos, and there can be overall randomness in spite of local appearances to the contrary. But it's not clear that the natural/artifact distinction is really to the point, nor the ancient/recent distinction. It's a matter of the patterns and their structure or lack thereof.

Wow, fantastic email -- getting at the heart of some major philosophical ideas and movements. Empiricists tend to stress the role of perception/experience in producing knowledge, while rationalists tend to promoe the role of reason, often arguing on the basis of such considerations as those you mention. A couple of quick thoughts about the specifics of your message. Your example of a problematic perception (spinning cube looks like sphere) doesn't quite/fully show that perception is problematic, partly because some other perception is relevant to getting at the truth, ie seeing the cube not spinning. The rationalist might say that reason is needed to process these otherwise conflicting perceptions, but even if this so, it does seem that perception is playing a key role in generating our knowledge of the world (that a cube exists, and that, when spun, it looks spherical) -- so what you've raised is a kind of problem for perception, but not one which obviously (to me anyway) undermines the importance of eprception in generation knowledge. Second, you mention the 'gap' between reality and minds -- and probably need to say more there. Even if everything we come to know about the empirical world were ultimately, in some way, derived from perception, it remains possible that perception is 'veridical' -- gives us true information about the world -- so the sheer fact that our access is mediated via perception does not entail that perception isn't veridical, or even direct .... This doesn't fully answer your excellent question -- how do we know we have knowledge not just perception? but aims to suggest that perception may well play important roles in generating knowledge despite the two kinds of worries you raise ....

hope that helps!

best,

Andrew