So, we just covered science, which is about things invariable, things which never come into being and always stay the same (i.e. the laws of Nature). Now let us talk about art, which is about things which do come into being (because they are made) and these things can come out in different ways, depending on certain things (e.g. who is the person making them). And let us also think about virtue. Both art and virtue are about things variable, they are the same in that respect, and so we must also look to also figure out how they are different.

Let us first get straight the difference between acting and making. Virtue is the ability to act. Art is the ability to make. Acting is something that comes from habits and is done for its own sake. Whenever the opportunity to take a virtuous action comes up, the virtuous person does it. A liberal person, for instance, enjoys giving friends help, by giving the right amount. When a friend in need comes to the liberal person, that liberal person is ready to do the liberal thing, and they give rightly. What that amount is does not matter, what matters is that it is the right amount.

Making, on the other hand, is concerned with the thing to be made, and not the movements made by the maker. The movements are determined by the plan of the maker and the plan comes from the thing that the product is wanted for. Take bridle-making, for instance. Bridles are used to ride horses. It is for that reason (viz. horse-riding) that a bridle-maker will make a bridle. A bridle-maker does not start twisting ropes for the sake of twisting ropes.

With making, something new gets brought into existence (1) from the things that it is made out of and (2) by the one that makes it. That is not the case with acting. Consider, for instance, a quantity of gold. A mediator of some kind may distribute the gold between the people who earned it. The mediator takes an action and makes a distribution that is either just or unjust. In this case of distribution, action is taken, but nothing gets produced. On the other hand, that same gold may also be melted down and cast into the form of a gold statue. In this case, something new does get produced. A statue is brought into being. But making the statue is not an action (not in the sense that we are using the term), because people do not always take gold, melt it down, and make it into statues for the sake of doing just that.

And note that things do not come into existence all by themselves. The cause of them coming into existence is the person that makes them (e.g. the artist, the builder, the craftsman).

All art is about bringing things about. The art of Medicine brings about health in a patient. The art of Politics brings about the laws of the State. And whatever the art, the person doing the work might or might not get the thing done right: that person may do the thing well, or they may do it ill, or they may fail to get it done at all.

No art is about things which come into existence because they must do so (i.e. something which comes into existence by necessity); and no art is about things which are brought into existence by something that is simply following its own nature. A bird, for instance, will build a nest, but a bird cannot be said to have the art of Nest-Making. The bird builds its nest because it is in its nature to do so, and because Nature requires that the bird have a place for its eggs. We cannot say the same thing about humans and statues. Nature does not require that humans make statues, nor are humans born with an instinct for statue-building.

If you think about it, Agathon is right in saying: "Art loves chance and chance loves art." Chance is involved in the formation of a tree (no two trees look exactly the same), and yet a tree may happen to come out as beautiful as a statue, even though that tree had no need to be so beautiful. So likewise, in many of the arts, in the process of making the thing chance will enter in, so no two products will appear exactly alike, and it is chance that is responsible for surprising and unexpected beauty in the thing made. And, generally speaking, the products of art may happen to be used for different ends than what they were intended. A container may be made for one thing, and once it has been emptied, may happen to be used to store something else; it was never made for that thing to begin with, but it so happened that it was useful for that end and was handy at the time when it chanced to be needed. Again, "art loves chance and chance loves art", and both chance and art are about things that are variable (and not fixed).

So, again, art is about bringing things into existence by correctly working out what has to be done in order to make those things come to be. Lack of art is the opposite. Lack of art is about incorrectly working things out and, while it may still bring things about, they are not what they ought to have been; perhaps they do what was intended, but poorly, or perhaps they do not work at all. Both of them, art and lack of art, are about things which are variable, which may come out in either one way or another.