How do Emile's two artistic passions shape him? How do they complement his attraction to both Cait and Gabrielle?

Émile believes that, in his art class, "his style was the exact opposite of his technical work; his line was loose, economical, free. And he wanted to capture what he couldn't keep, the fleeting, the transient." He believes, of his engineering, that "there was finesse in his composition of girders and blots; it was bold and brilliant, it was art." How do these two artistic passions shape him? How do they complement his attraction to both Cait and Gabrielle?

Even though Emile had the ability to create and appreciate art forms that appeared light and free, there was also a tremendous amount of technique and technical knowledge involved. He was proud of the technical expertise required to build the Tower, but seemed to almost take it for granted, and aspire to larger achievements. So maybe his base level knowledge (including his rather negative assessments of sometimes pretentious Impressionist artists) equated to the lower plane of achievement, characterized by Gabrielle and Alice); his higher-level aspirations, the true artists and the overriding impression of the completed Tower, corresponding to Cait. I thought that bringing Cait, Alice, and Jamie into the art scene was one of the less successful parts of the novel, while the Tower technical details and insider conversation were more believable.