Science and Art: A Bad Combination?

Martin Jay defines Cartesian perspectivalism as a combination of "Renaissance notions of perspective in the visual arts and Cartesian ideas of subjective rationality in philosophy" and discusses this in fair detail in the beginning of the article. Why did he use the word "Cartesian"? Was "perspectivalism" not proficient in describing the practice of art in question? What does "subjective rationality in philosophy" have anything to do with this? I thought that the essence of his arguments against Rennaisance paintings was that it focused on dry, mathematical and emotionally-detached elements rather than the more significant emotional, personal elements powered by creativity of the artists. How philosophy ties into this, I do not know, but this idea of "subjective rationality" already breathes life into what Jay implies to be dull, even almost lifeless, form of art because "subjective" suggests "personal." Already in the beginning of the article, I felt dismayed by this seemingly paradoxical term that Jay adopted.
Maybe because I read this article through the lens of a scientist, I found this disagreeable. It seemed as though Jay considered science and mathematics as somewhat lesser subjects because they apparently lack some sort of personal connection to the audience. It most likely wasn't the point Jay was trying to make, but that similar idea carried through to his opinions about Renessaince art. Not only does he discuss the problems of "Cartesian perspectivalism" that spring from its too close of a relationship to mathematics and science (which happen to be dry, apparently) but he also pushes it as far as referring to Edgerton who argues that it was "no accident that the invention (or rediscovery) of perspective virtually coincided with the emergence of the oil painting... available for buying and selling." It seems to me that Edgerton (and I think Jay agrees) is somehow blaming Cartesian perspectivalism for reducing art from its pure, unearthly and beautiful state to somehow evil, common and commercial state. This is only a specific example I am providing, but the overall impression I got from this article was that because Cartesian perspectivalism consists of too much of science and math and not enough of what he considers art, it is a lesser form of art. And I think a lot of people agree with Jay. I appreciate art very much, and I don't think that art necessarily has to be a complex entanglement of the artist's emotions and what not (people often seem to think that if you don't understand something, then that means it's "deep" and "artistic"). Beauty can be found in those Renaissance paintings, just like how we can find beauty in the elegance and simplicity of the scientific descriptions of the world.