Thomas Aquinas

“ Intention is an act of the will in regard to the end. Now the will stands in a threefold relation to the end. First, absolutely; and thus we have "volition," whereby we will absolutely to have health, and so forth. Secondly, it considers the end, as its place of rest; and thus "enjoyment" regards the end. Thirdly, it considers the end as the term towards which something is ordained; and thus "intention" regards the end. For when we speak of intending to have health, we mean not only that we have it, but that we will have it by means of something else. ”

“ According, therefore, as that which is moved to an end by another is said to intend the end, thus nature is said to intend an end, as being moved to its end by God, as the arrow is moved by the archer. ”

“ And if they be ordained to one another, it is evident, from what has been said, that a man can intend several things at the same time. For intention is not only of the last end, as stated above (A [2] ) , but also of an intermediary end. Now a man intends at the same time, both the proximate and the last end; as the mixing of a medicine and the giving of health.
But if we take two things that are not ordained to one another, thus also a man can intend several things at the same time. This is evident from the fact that a man prefers one thing to another because it is the better of the two. ”