Kierkegaard was not a systematic philosopher, but is generally considered the first philosopher.

There were many differences between the philosophers that that are associated with existentialism but it is considered that the first existentialists philosopher was Søren Kierkegaard. He believed it was a duty and a responsibility of the individual to give his life meaning and to live it authentically. For existentialists as a whole a sense of dread, fear, of disorientation, confusion in the face of an apparently absurd and along with it a meaningless life and world is a starting point in achieving authenticity.

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