Hedonism becomes the default lifestyle.
Why? Do people who believe in a god have so little self-control, such a lack of an innate moral compass, that they would be come hedonists if convinced their god was not real? Is the only thing keeping a god-believer in line his belief in that god? If so, it would seem that the atheist is morally superior, since his moral sense is self-determined.
Without immortality, life is meaningless and absurd.
On the contrary, the knowledge that life is finite and that there is no afterlife imbues this life with all the deep, poignant meaning that brief pleasures generally bring.
On the contrary? It sure sounds like hedonism to me.
You need some more Bertrand Russell
That Man is the product of causes that had no prevision of the end they were achieving; that his origin, his growth, his hopes and fears, his loves and his beliefs, are but the outcome of accidental collocations of atoms; that no fire, no heroism, no intensity of thought and feeling, can preserve individual life beyond the grave; that all the labors of the ages, all the devotion, all the inspiration, all the noonday brightness of human genius, are destined to extinction in the vast death of the solar system, and that the whole temple of Man's achievement must inevitably be buried beneath the debris of a universe in ruins — all these things, if not quite beyond dispute, are yet so nearly certain that no philosophy which rejects them can hope to stand. Only within the scaffolding of these truths, only on the firm foundation of unyielding despair, can the soul's habitation henceforth be safely built.If that self-refuting nonsense is not enough to make you go insane or kill yourself I don't know what is.
Cordially