In ‘Can and Might’ (this Journal, vol. 1, no. 1, September, 1971, pp. 87–92), Professor K. W. Rankin has presented three arguments that purport to refute the equivalence (E), ‘A (an action) is causally possible for P (a person) if and only if A is within P's power’. The first two arguments are attributed to Richard Taylor (Action and Purpose, Prentice-Hall, 1966, pp. 53–59), and the third is Professor Rankin's own. I will argue that none of these three arguments effectively refutes the above equivalence. My arguments are not to be construed as simply a rebuttal of Professor Rankin's paper since (a) he also appears to have some doubts about Taylor's arguments and (b) I refrain from comment on other aspects of his paper except these three arguments. I conclude with some general remarks on (E).