Søren Kierkegaard

Widely regarded as “the father of Existentialism”, Kierkegaard revolutionized philosophy by challenging its fundamental premises and purposes. While the philosophers before him asked “how”, he asked “why”.
Kierkegaard confronted the traditional notion of knowledge and pushed for a more subjective truth. What good is some abstract concept if it does not effect your life? We cannot know if God exists by the very definition of God, so how does belief in God change my life, my logic, and my personal happiness? We cannot know objective truth, nor can we control it, but we can control our experience of the world. That is truth. Truth is experience.
Kierkegaard published like a man possessed and his books are notoriously hard to understand. He will often argue multiple sides, with no definite conclusion, and is prone to long illustrative stories or fantastical monologues. But plow through his dense writing and you will be rewarded with one of the most relevant, lyrical, and exciting philosophers to have ever put pen to paper. Kierkegaard is a philosopher for the modern age and he still has a ton to offer scholars and students that hasn’t even yet been fully understood.