This paper intends to examine Aristotle's conception of the 'now', such as it is presented in Physics IV 10-14. The author argues that in the two main issues Aristotle tackles there (that is, whether time exists and what time is) the now is understood as being an inner limit of time, an understanding where the main emphasis is upon the condition of indivisibility of such a limit or, in other words, upon the fact that the now is not part of time. Baño concentrates on the analogy between 'now' and moving body, presented by Aristotle in order to account for the difficult thesis that the 'now' is always the same and, at once, always different. The issue the author is particularly concerned with is the fact that the moving body does not appear to be the same to movement as the 'now' is to time, since the moving body is not an inner limit of movement. Consequently, the analogy cannot be based on the punctual condition of the 'now', and rather it seems to be based on the fact that the 'now' is a principle of time cognition, such as the moving body is a principle of cognition of movement. [ABSTRACT FROM AUTHOR]