I have previously noted that when Hume rejects the notion that we get the idea of causation from our sense of resistance, he gives the following as part of his reason for doing so:
But, first, we attribute power to a vast number of objects, where we never can suppose this resistance or exertion of force to take place; to the Supreme Being, who never meets with any resistance; to the mind in its command over its ideas and limbs, in common thinking and motion, where the effect follows immediately upon the will, without any exertion or summoning up of force; to inanimate matter, which is not capable of this sentiment.
And I noted that this fails to do adequate justice to what can be concluded by analogy, and also that the case of the Supreme Being, given Hume's own account of our idea of God, really stands or falls with the case of the mind's command over its ideas. There is an additional problem with the latter that is also worth noting.
Malebranche, in the Dialogues on Metaphysics and on Religion, has an interesting passage in which he does precisely what Hume says in the above passage that we do not do, namely, attribute resistance to the case of the mind's command over its ideas:
But do you think your ideas do not resist you? Find me then two unequal diameters in a circle, or three equal ones in an ellipse. Find me the square root of eight and the cube root of nine. Make it just to do unto others what is unacceptable to ourselves; or, to take an example more suited to you, make two feet of intelligible extension equal no more than one. Certainly the nature of this extension cannot countenance that. It resists your mind. (DMR 1.8, Jolley-Scott p. 14)
He claims, in fact, that the primary difference between the floor resisting the foot and ideas resisting the mind's attempt to force them is that perception of the former is obscure and perception of the latter is clear.
Hume, I think, has very limited room with which to reject a position like this, because in order to head off a different kind of argument that the idea of causation derives from our experience of the mind's command over its own ideas, he explicitly emphasizes that we find that "The command of the mind over itself is limited, as well as its command over the body". How is this limitation of command experienced? The resistance of our ideas to our mind's manipulation of them seems a plausible answer. In the same way, if you are trying to move your arm but are finding it paralyzed, it seems that this could also be experienced as a kind of resistance. Even where it is not impossible to force our mind to think a certain way, or to move our body a certain way, you can still have some kind of resistance; it would be simply false to say that people don't think you ever have to "summon up force" in such cases.
