I believe this paragraph illustrates Rand's view of the uniqueness of the individual and how it is that uniqueness that is immortal. Roark represents individualism in the novel and Rand views this as being more noble than collectivism. The group mentality results in mediocrity - the "unformed mass" as she calls it. Roark, on the other hand, refuses to let the collective sway him from his indiviual path in life. His life has been one of swimming upstream, against the current of collectivism. He fails to graduate from college but it is no big deal to him because he claims he never learned anything important there anyway. He esschews money but yet achieves a more important goal because his designs, his work illustrate vision, passion, whereas Keating's do not. Keating must resort to manipulation to succeed, whereas Roark succeeds because he is unique. Everything else is measured against him in this novel - thus, he is a true "fountainhead" - a source.
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