Existentialist philosophers argue that existence has a meaning and value of its own, separate from traditional metaphysical doctrines. This position counters the claims of nihilism that the failures of philosophy inevitably prove the meaninglessness of life. Kierkegaard said that what truly mattered was the individual in relation to eternity. Nietzsche posed the question of the eternal return, asking how we would choose to live if we knew our actions would be repeated forever. Camus said that even the total futility of life was not a good reason to commit suicide.
Existentialists emphasize the importance of humans acting freely to shape their own character and destiny. This stands in contrast to nihilism, which claims that life is reducible to the random collisions of particles. Kierkegaard said that every individual is faced with a profound choice which goes beyond the authority of any religion or state. Sartre wrote of humanity as "condemned to be free" and said that we have the power to choose our response to any circumstance. Nietzsche said that true strength came from living a life of creative purpose rather than one driven by guilt and fear.
Traditional beliefs about right and wrong need to be challenged, according to existentialist philosophers, while nihilists argue that the very notion of acting morally is meaningless. Kierkegaard gave the example of Abraham and Isaac from the Bible and said that this proves that real faith is not captive to formulaic ethical doctrines. Nietzsche said that traditional morality had been used to justify shameful indifference to suffering and a herd mentality. Sartre became involved in the effort to prevent nuclear war and said societies should promote greater equality.
Each of the existentialist philosophers blamed religious institutions for many of society's problems, saying that corrupt religious authorities had damaged the ability of individuals to think for themselves and care for others. This differs from nihilism, which denies any positive quality to religion, spirituality or faith. Kierkegaard said that churches should be places of conscience and seeking rather than hallways of power. Nietzsche speculated that the decline of traditional religion would give rise to a new kind of prophetic faith. Sartre said that the disappearance of God had taken away humanity's last excuse to avoid responsibility.