Some philosophers (e.g John McDowell) argue that the content of perceptual experience is necessarily characterized by conceptual terms; namely - the content of the experience is entirely built of concepts possessed by the subject of experience. Others (e.g. Hubert Dreyfus) claim that there are necessarily some aspects of the perceptual experience which cannot be characterized as conceptual.
My question: To what extent the content of our perceptual experience is conceptual? Are there any examples demonstrating that some facets of perceptual experience cannot be characterized as conceptual? What do we have to assume in order to arrive at a conclusion that perceptual experience must be conceptual "all the way down" ?
(1) In light of a comment received below - let me further clarify: The notions of 'concept' and 'experience' belong to abstract and concrete realms respectively. The question I posed seeks to find out - in what ways a perceptual experience can or cannot be devoid of concepts? (The question could be seen in some way as parallel to the question of the relation between theory and observation; though the one I raised is more basic)
(2) My current tentative conjecture is that if we talk of some kind of religious experience than we have an extreme example of some possibly perceptual experience that is devoid of concepts by means that it is ineffable. But I will welcome any other directions - perhaps such that are drawn in addition from philosophy of language, philosophy of mind, phenomenology and philosophy of science.