Esthetics (from the Greek αίσθητικóς, sensible) is the philosophical discipline having as its object the domain of expressive form of any sphere of reality (including the artistic), given as an independent and directly perceptible value. The term "esthetics' was first used by Baumgarten (Aesthetica, Bd. 1–2, Fr/M., 1750–1758) to designate the 'science of sensible knowledge" which, as an "inferior theory of knowledge" (gnoseologia inferior), was to complement the logic of Wolff. It was in this sense that Kant called it the science of "the rules of sensibility (Sinnlichkeit) in general" (a meaning preserved even in Husserl"s works). However, along with this meaning derived from Baumgarten, there is the other use of "esthetics' to designate the philosophy of artistic creativity — a definition reinforced by Hegel's Lectures on Esthetics.