Having defined liberty (freedom) as the power to do or forbear doing any particular action as the person prefers or wills, Locke was able both to defend liberty (so conceived) and to allow the particular act of will or preference of the mind to be totally determined by causes within and without the agent. In a revealing passage in the first edition of An Essay Concerning Human Understanding Locke notes that the absolute determination of the will or preference of the mind does not preclude freedom so far as the action flowing from the will or preference of the mind is concerned.

But though the preference of the Mind be always determined.., yet the Person who has the Power, in which alone consists liberty to act, or not to act, according to such preference, is nevertheless free; such determination abridges not that Power. He that has his Chains knocked off, and the Prison doors set open to him, is perfectly at liberty, because he may either go or stay as he best likes; though his preference be determined to stay by the darkness of the Night, or illness of the Weather, or want of other Lodging. He ceases not to be free; though that which at that time appears to him the greater Good absolutely determines his preference, and makes him stay in his Prison?