The Gnat and the Bull

A Gnat had settled to rest on the horn of a bull for a long time. Before he left, he spoke to the bull,"Would you like me to go now?"

"Oh, never trouble your head about that," says the Bull, "I didn't notice when you came, and now that you are leaving, I shall not miss you; and, to say the truth, I did not know you were there."

Moral

The smaller the mind, the greater the conceit.

or

Those of little capability often think themselves to be of greatest consequence.