Abstract
In this paper I argue that, according to Peirce’s mature account of perception, we directly perceive generals, or "Thirds," in external reality which should be described as physical and not as mental. I argue against three other interpretations of the role of Thirdness in Peirce’s account: (I) we do not directly perceive Thirds, although they are involved in the interpretive and judgmental part of perception; (II) we directly perceive Thirds, but they are imposed on external objects by our minds; and (III) we directly perceive Thirds in external objects, but external reality is comprised of the representations of an objective mind. I address questions about the role of the percept and the percipuum in his account, in what exact sense he thought that perception is interpretive, and how he thought it is even possible to directly perceive generals in the external world.