Abstract
By introspection here is understood a direct access to the phenomenal character of one's mental states, or qualia. Its introduction to the philosophy of mind is motivated by the apparent impossibility of vindicating the existence of qualia by any other means, but that being the sole explanatory purpose of introspection, it makes the notion circular.
Any account of it contains a paradox: if introspection is defined as an externally non-derivable, privileged access to qualia, it has the same characteristics as qualia themselves, namely, non-derivability from externally accessible facts, and, therefore, dubious explanatory value; if, on the other hand, it is understood in the externalist terms, it loses the privileged point of view which motivated its postulation in the first place. The paper's aim is to introduce a Peircean solution to the problem: while Peirce's inferential theory of knowledge rejects introspection, his analysis of sign-constitution allows positive means for acknowledging qualia.