Aristotle, as stated in the last post, held that the highest knowledge is for its own sake, not for the sake of other things. Francis Bacon, on the other hand, is famous for saying that knowledge is power (Novum Organum, Bk. 1, Aphorism 3):
Human knowledge and human power meet in one; for where the cause is not known the effect cannot be produced. Nature to be commanded must be obeyed; and that which in contemplation is as the cause is in operation as the rule.
Although Aristotle is correct regarding the purpose of the sciences, this difference between the two of them may partly explain their difference of opinion regarding the state of completeness of the sciences. Aristotle basically believed the sciences complete, as I said in the last post, but part of the reason for this may be that he did not care much about potential improvements in the mechanical arts. Bacon, on the other hand, was concerned precisely with such improvements. In particular, he wishes to make gold, as he suggests here in Bk. 2, Aphorism 5:
The rule or axiom for the transformation of bodies is of two kinds. The first regards a body as a troop or collection of simple natures. In gold, for example, the following properties meet. It is yellow in color, heavy up to a certain weight, malleable or ductile to a certain degree of extension; it is not volatile and loses none of its substance by the action of fire; it turns into a liquid with a certain degree of fluidity; it is separated and dissolved by particular means; and so on for the other natures which meet in gold. This kind of axiom, therefore, deduces the thing from the forms of simple natures. For he who knows the forms of yellow, weight, ductility, fixity, fluidity, solution, and so on, and the methods for superinducing them and their gradations and modes, will make it his care to have them joined together in some body, whence may follow the transformation of that body into gold.
This desire for gold in particular is probably a desire for money, which seems to be a kind of universal power, although one might question whether money would be necessary for someone who can change anything into anything else whenever he pleases. In any case, Bacon is engaging in a kind of wishful thinking here. He recognizes, in fact, that human beings have a limited ability to transform nature (Bk. 1, Aphorism 4):
Toward the effecting of works, all that man can do is to put together or put asunder natural bodies. The rest is done by nature working within.
From this it should follow that it may be impossible to effect certain transformations, if they will not follow upon such putting together or asunder of natural bodies. But instead of waiting to learn from experience, Bacon simply assumes (and this is the wishful thinking) that any possible transformation, such as the transformation of lead into gold, will definitely be possible. Since the sciences of his day could do nothing of the sort, he concluded that the sciences still had a great deal of room for improvement.
There are good reasons to think that Bacon’s assumption was false. For example, the no-cloning theorem says that perfectly copying a quantum state is impossible. There may be no particular reason why you would need to do this, but that is not the point. Rather, Bacon claims that any form can be induced upon anything, and this seems to be false.
Nonetheless, his conclusion that the sciences of his day were very imperfect was indeed correct. Thus, although his idea of the purpose of the sciences was inferior to Aristotle’s position, his idea of the state of their progress was superior.