An imaginary conviction that this or that thing is true, even if such conviction be based upon the strongest reasons of plausibility and probability, is no real knowledge or self-recognition of truth. The truth is really known to no man until it is realized in him; but when the light of truth arises as a living power within his soul, penetrating and illuminating his understanding, causing him to enter into full harmony and become one with the truth, he may then truly say, not only “I know the truth,” but like one of old, “I [in my personal state] am the Truth.” This, however, is not to be interpreted as if to mean that we should reject all theories or treat opinions of others with contempt. Theories are means by which to arrive at practice; they are like crutches used by children before they are able to walk. They are sometimes good for discarding errors; but a knowledge of theories is not identical with the recognition of truth.

Franz Hartmann, The Correlation of Spiritual Forces