What is Orwell's purpose in Part One of 1984 and how do the contrasts he creates help establish that purpose?

Orwell sets context for the dystopian world of Oceania in part one. We get to know Winston and the precarious position he inhabits at the Ministry of Truth. We understand his angst-ridden intellect in a society that demands thoughtless conformity. We see the futility of attempting change and the faint hope that Winston puts in O’Brien.