As Peirce said, almost all the philosophers of the nineteenth century (after Kant) have agreed to name Feeling, Knowledge, and Will as parts of the mind, or to put it more accurately, as the three classes of states of mind (CP 7.564). But, in his view, the feeling is nothing but the inward aspect of things, while the mind, on the contrary, is essentially an external phenomenon (CP 7.364). What he understands by consciousness is really in itself nothing but feeling (CP 7.364). According to Peirce, one part of sensation is feeling, and the other part is the consciousness of being compelled to feel (CP 7.545). Also, concepts are nothing more than a different kind of qualities of feeling (CP 5.501). On the other hand, any concept is a sign, and we may even so enlarge the meaning of a sign that its interpretant is a mere quality of feeling (CP 8.332). It is the case of the aesthetic sign whose interpretant is the emotional interpretant. Through this, in my opinion, Peirce opens the way to the possibility of aesthetic knowledge, not only as a kind of knowledge but as a fundamental one.