Descartes and Rationalism

Modern rationalism begins with René Descartes, whose famous claim “I think, therefore I am” made human self-consciousness the starting point of reality. Instead of God creating and defining all things, man’s thinking became the judge of what is real. God was reduced to an object that must be validated by human reason, laying the groundwork for the modern idea that God can be “created” or dismissed by man. This logic was developed further by Kant and Hegel, leading to the belief that the rational is the real. The result is a worldview in which man, not God, stands at the center, severed from the authority of the past, divine revelation, and moral consequence. Existentialism followed naturally, stressing the isolated moment and denying lasting meaning, accountability, or future hope. Cartesian rationalism ultimately collapses into irrationality, shrinking both theology and human life by exaggerating man’s powers. Christianity must reject this man-centered starting point and return to the Biblical foundation: God’s revelation, not human reason, is the source of truth, meaning, and reality.