In describing Kant's idea of the "thing-in-itself" Thomas Pogge (in response to a recent question on this site) recently wrote that "According to this explanation, space and time are then features only of objects as they appear to us." I'm having a difficult time deciphering this statement. To me when you speak of a feature of an object you are referring to that object in-itself almost by definition. It seems like space and time could be either a feature of the world or a feature of our mind/cognition or psychic tendencies which we project onto the world but not both. To say that space/time is a feature of the world as it appears seems to involve a confusion of how language is used to speak about being. Appearances can reveal or distort being but I don't see how they can contribute to being. We don't speak of colors as features of the (outer) world as they appear to us do we? We try to figure whether colors originate in the mind or in the world and though we allow that there is some degree of interaction...

You are quite rightly puzzled by the distinction that Pogge, following Kant, draws between appearances and things-in-themselves: it's caused trouble for Kant's readers since the publication of the first edition of the Critique of Pure Reason . The distinction is, however, at the heart of Kant's project in the first Critique , and indeed, I would go so far as to claim that it's crucial to underpinning the entire Critical philosophy. (I see the first Critique as setting the foundations for Kant's overarching project, which I take to be aimed at ethics rather than at metaphysics and epistemology. This is a somewhat idiosyncratic view, but it is, I think, defensible; in any event, nothing in what follows turns on it.) Now the distinction that Kant wants and needs to draw is between the world as it is independently of human cognizers, and the world that appears to human beings. Yet Kant does not want to claim that the way things appear to human beings is merely a way that they appear, as...

Is it possible to perceive something unconsciously?

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...

Does synesthesia have any significant implication for philosophies of perception?

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...