Here’s a quote from Scanlon:
A rational person who judges that there to be sufficient grounds for believing that P normally has that belief, and this judgment is normally sufficient explanation for so believing. There is no need to appeal to some further source of motivation such as “wanting to believe.” (Scanlon 1998, 33)
Immediately following this quote, Scanlon goes on to say that the same is true of intending to do x. We don’t need to appeal to a desire to explain why someone who judged that there was sufficient grounds for intending to do x intended to do x.
Now here’s an observation: no one, not even the Humean, would appeal to something like “wanting to intend to do x” (the analogue of Scanlon’s “wanting to believe”) in order to explain why someone has formed the intention to do x. I take it that if we do think that we need to appeal to some desire, it will be a desire for some states of affairs that the agent aims to bring about by doing x, not to a desire to intend to do x. The thought is that purposive actions aim at the realization of states of affairs and thus the motivation for such action lies with a desire for the state of affairs that’s being aimed at. This brings out an important difference between intending to do x and other attitudes such as desiring that P, believing that P, admiring S, etc. Whereas the attitude of intending to do x is telic, these other attitudes (desiring, believing, admiring) are not. For instance, when we believe that P, we don’t do so for the sake of realizing some end. By contrast, when we intend to do x, we do so for the sake of realizing some end.
Now here’s a question: Does the fact that the attitude of intending to do x is telic whereas these other attitudes (e.g., believing and desiring) are not give credence to the view that we must appeal to a desire for some end in explaining why someone has formed the intention to do x but not to explain why someone has formed these other attitudes (e.g., the belief that P or the desire that P)?