What is the root of all actual, personal sins? What is the source of nihilism? Hear Augustine on the matter.
“Now, could anything but pride have been the start of the evil will? For ‘pride is the start of every kind of sin’ (Ecclus. 10:13). And what is pride except a longing for a perverse kind of exaltation? For it is a perverse kind of exaltation to abandon the basis on which the mind should be firmly fixed, and to become, as it were, based on oneself, and so remain. This happens when a man is too pleased with himself: and a man is self-complacent when he deserts that changeless Good in which, rather than in himself, he ought to have found his satisfaction…And so, to abandon God and to exist in oneself, that is to please oneself, is not immediately to lose all being; but it is to come nearer to nothingness”
City of God, Book XIV, Ch. 13