In this paper I argue that Alexander, while being generally faithful to Aristotle’s regarding the common sense, made four lasting contributions to this topic. First, he restricted the term ‘common sense’ to the unified perceptual power of the soul which excludes phantasia. This blazed the trail for later theories of the internal senses in which the common sense figures as a non-rational cognitive capacity distinct from phantasia, memory, and whatever further capacity various Arabic and Latin philosophers may have postulated. Second, Alexander’s claim that we perceive ourselves seeing and hearing by means of the common sense, rather than by the special senses, influenced (correctly, in my opinion) later readings of Aristotle’s passages dealing with awareness of perception, giving preference to Aristotle’s account in De somno 2 over his more widely read account in De anima III.2, 425b12-25. Third, his statement that the common sensibles are perceived by the common sense, rather than by the special senses, made its mark (incorrectly, in my opinion) on later readings of Aristotle’s passages dealing with the common sensibles, most notably of De anima III.1, 425a14-425b11. Fourth, Alexander’s analogy of the common sense with the centre of a circle in which different radii meet, though surely inspired by Aristotle’s analogy of a point bisecting a line in De anima III.2, 427a9-14, was a brilliant innovation that intuitively captured the Peripatetic cardiocentric model, leaving a deep impression on later students of Aristotle.