Irrationalism denies the possibility of truth

"Irrationalism, fostered by such men as Soren Kierkegaard (1813-1855), Friedrich Schleiermacher (1768-1834), and neo-orthodox theologians, is a form of skepticism. It is antirational and anti-intellectual. Actual truth, say the skeptic, can never be attained; rational attempts to explain the world leave us in despair. Reality cannot be communicated propositionally, it must be grasped 'personally and passionately' (Kierkegaard); truth must be sought in inward experiences, that is, subjectively." - W. Gary Crampton, The Scripturalism of Gordon H. Clark, Pg. 24.