…I conceive that in all deliberations, that is to say, in all alternate succession of contrary appetites, the last is that which we call the will, and is immediately next before the doing of the action, or next before the doing of it become impossible. All other appetites to do and to quit that come upon a man during his deliberation are usually called intentions and inclinations, but not wills… (LN 37)
So, for Hobbes, the will is not exactly a faculty. It is a term we use to label appetites, when they play a certain role: the role of concluding a session of deliberation. Deliberation, in turn, is “nothing but alternate imagination of the good and evil sequels of an action, or, which is the same thing, alternate hope and fear or alternate appetite to do or quit the action of which he deliberates” (LN 37).
It’s important to note that Hobbes does not see deliberation as fundamentally tied to the intellect, or even to distinctly rational appetites. He sees it as grounded in a process of warring appetites—and he does not limit the appetites involved to rational ones. (Indeed, it’s not clear that Hobbes wants or needs any distinctions between natural, sensitive, and rational appetites.) For Hobbes, even “bees and spiders” are able to deliberate; their appetites drive them toward action in response to “hope of greater good,” and away from action in response to “fear of greater evil” (LN 19). Admittedly, these hopes and fears are pre-linguistic. But as long as they can be in some way represented by the murky imagination of a spider, that spider can will to act; after all, he can act on the basis of a final appetite, which is the very definition of willed action. So Hobbes offers a rather skeletal set of requirements for human willing, and there is nothing necessarily human about any of these requirements.