The word aesthetics did not exist as the name of a philosophical discipline until a German philosopher decided the study of sensory perception and beauty needed one. In his 1735 dissertation Meditationes philosophicae de nonnullis ad poema pertinentibus, Alexander Baumgarten coined the term aesthetica, from the Greek word for sense perception, to name a proposed science of sensory cognition standing alongside logic, which he treated as the science of the higher, rational cognitive faculty. Where logic governed clear and distinct conceptual thought, Baumgarten argued that sensory experience, including the perception of beauty in art and nature, follows its own kind of perfection and deserved its own systematic philosophical treatment rather than being dismissed as a merely confused version of rational knowledge.
Baumgarten expanded the project into a full, if unfinished, treatise, the Aesthetica, published in two volumes beginning in 1750, and though the book itself found few close readers in its own era, the discipline he named outgrew him within a generation. Immanuel Kant, initially skeptical that taste could be the subject of a genuine science, eventually adopted Baumgarten's term for his own very different account of aesthetic judgment in the 1790 Critique of Judgment, and it is Baumgarten's word, not his particular theory, that survived into every later philosophical vocabulary for the field: aesthetics remained the name for the philosophical study of beauty and art long after the rationalist framework Baumgarten built it to serve had been argued away.