Example 1: self-play. AI is not just human level at chess, it far exceeds human level because of self-play. Example 2: aggregation of peak performance. No human can get all math Olympiad problems right; but an A.I. can be trained on the correct answers to all math Olympiad problems. Example 3: aggregation of knowledge. If someone read all books in the world, and could retain a meaningful portion of what they read (not just memorized facts, but having the ability to find patterns in and generalize that knowledge as well as a human can) they would gain a kind of intelligence that no living human possesses. (source)