Affect (from Latin affectus or adfectus) is a concept, used in the philosophy of Baruch Spinoza and elaborated by Henri Bergson, Gilles Deleuze and Félix Guattari, that places emphasis on bodily or embodied experience. The word affect takes on a different meaning in psychology and other fields.
For Spinoza, as discussed in Parts Two and Three of his Ethics, affects are states of mind and body that are related to (but not exactly synonymous with) feelings and emotions, of which he says there are three primary kinds: pleasure or joy (laetitia),[1] pain or sorrow (tristitia)[1] and desire (cupiditas) or appetite.[2] Subsequent philosophical usage by Gilles Deleuze, Félix Guattari and their translator Brian Massumi, while derived explicitly from Spinoza, tends to distinguish more sharply than Spinoza does between affect and what are conventionally called emotions. Affects are difficult to grasp and conceptualize because, as Spinoza says, "an affect or passion of the mind [animi pathema] is a confused idea" which is only perceived by the increase or decrease it causes in the body's vital force.[3] The term "affect" is central to what has become known as the "affective turn" in the humanities and social sciences.