The axiom that every effect must liave a cause, or the doctrine of a sufficient reason, applies to the internal as well as to the extei-- nal world. It governs the whole sphere of our experience, inward and outward. Every volition is an effect, and therefore must have had a cause. There must have been some sufficient reason why it was so, rather than otherwise. That reason was not the mere ])0wer of the agent to act ; for that only accounts for his acting, not for his acting one way rather than another. The force of gravity accounts for a stone falling to the earth, but not for its falling here instead of there. The power to walk accounts for a man's walking, but not for his walking east rather than west. Yet we are told even by the most distinguished writers, that the efficiency of the agent is all that is required to satisfy the instinctive demand which we make for a sufficient reason, in the case of our volitions. Reid, as quoted above, asks, " Was there a cause of the action ? Undoubtedly there was. Of every event there must be a cause that had power sufficient to produce it, and that exerted that power ,for the purpose. In the present case, eitlier the man was the cause of the action, and then it was a free action, and is jnstly imputed to him ; or it must have had another cause, and cannot justly be imjnited to the man. In this sense, therefore, it is granted that there was a sufficient reason for the action ; but the question about liberty, is not in the least affected by this concession."^ Again, he asks, " Why may not an efficient cause be defined to be a being that had ]:)Ower and will to produce the effect ? The prodixction of an effect requires active power, and active power, being a quality, must be in a being endowed with that power. Power without will produces no effect ; but, where these are conjoined, the effect must be produced."^ Sir William Hamilton's annotation on the former of these passages is, " that of a hyper-physical as well as of a physical event, we must, by a necessary mental law, always suppose
1 Actke Powers, Essay iv. ch. 9; Works, edit. Edinburgh, 18-19, p. 625.
2 Ibid. p. 627.