Helen Steward holds that agency is a power to move oneself, and that it is specifically a power to move one’s body. This conception of agency is supported by a long tradition and is widely held today. It is, however, opposed to another conception of agency on which agency is a power to transact with others—with other things and with other agents. The latter conception, though scarcely represented in contemporary action theory, is no less traditional than the one that Steward (...) prefers. In this paper I argue, first, that Steward’s official purposes do not require her to privilege self-movement over other-movement, as she resolutely does; and second, that the two touchstones of truth to which she appeals throughout her book—namely, ordinary thought and natural science—both recommend a conception of agency on which it is a power whose characteristic and definitive act is a transaction. abstract. (shrink)