I think there's a bit of confusion about what we're talking about when we say "sex." I'm not talking about the conscious desire to have sex. When I talk about sex, I'm talking about sexual selection which is the competition between members of the same species for sexual partners over many generations.
I'm not talking about the conscious motives of individual artists. Their conscious motives for creating art may be to "assert [their] existence," as you say.
I would argue that all of our physical and mental traits have arisen from the process of natural and sexual selection. If you accept that, you can also accept that over the generations, we have evolved the ability to be artistic, in many different ways. An individual who has inherited the ability to create good art, and does so, may not (and probably is not) creating art with the conscious goal of using it to attract sexual partners. However, if individuals of the opposite sex do find this ability (or side effects of this ability) attractive, they will be more likely to mate with the artistic individual, perpetuating the artistic genes. This is how I see art coming about because of sexual selection.
I'm not talking about the conscious motives of individual artists. Their conscious motives for creating art may be to "assert [their] existence," as you say.
I would argue that all of our physical and mental traits have arisen from the process of natural and sexual selection. If you accept that, you can also accept that over the generations, we have evolved the ability to be artistic, in many different ways. An individual who has inherited the ability to create good art, and does so, may not (and probably is not) creating art with the conscious goal of using it to attract sexual partners. However, if individuals of the opposite sex do find this ability (or side effects of this ability) attractive, they will be more likely to mate with the artistic individual, perpetuating the artistic genes. This is how I see art coming about because of sexual selection.