What Is Nick's Reaction To Gatsby Story- In Chapter 4- ?

Though Nick was first taken with Gatsby's seeming purity and optimism, Gatsby remains enigmatic and not entirely trustworthy. Gatsby's own account of his illustrious past seems, to Nick,  comically exaggerated. His readiness to provide evidence to corroborate his story is itself suspect; an honest man, one imagines, would be insulted by Nick's skepticism.