Ibn Qayyim said, “Whoever says, ‘I know’, is ignorant. I have discovered from my own experience that whenever someone increases in knowledge, they discover how much greater their ignorance is. The words of Allah are true when He says, ‘And they ask you, [O Muhammad], about the soul. Say, The soul is of the affair of my Lord. And mankind has not been given of knowledge except a little.’”

Abridgement of The Book of Souls by Ibn Qayyim