One of Turgenev's main goals in Fathers and Sons is to accurately portray a massive cultural struggle in mid-nineteenth century Russia. As the novel moves on, it is clear that he is not aiming at accuracy for the sake of accuracy. The goal is that such an accurate portrayal will also allow the reader to distill some wisdom from the narrative. As the characters age and grow humble through experience, they often speak wisely. But just as often the narrator breaks the bounds of "straight story-telling" so that he can pass on a kernel of wisdom to the reader.
As Bazarov becomes melancholy and then sick, he learns that wisdom is inseparable from suffering and a sense of one's own insignificance.
Pavel Petrovich's sense of wisdom as basic self-respect and respect for civilization at large is inherently bound up with a conservative viewpoint; there is no room for progress if one is weighed down by a sense of duty to what has come before.