a piece of the truth
One day Mara, the Evil One, was travelling through the villages of India with his attendants. He saw a man doing walking meditation whose face was lit up on wonder. The man had just discovered something on the ground in front of him. Mara's attendant asked what that was and Mara replied, "A piece of truth." "Doesn't this bother you when someone finds a piece of truth, O Evil One?" his attendant asked. "No," Mara replied. "Right after this, they usually make a belief out of it."