What is 'The Son of Man' by Rene Magritte?

The Son of Man, 1964 is an oil on canvas artwork by Rene Magritte (1898-1967).

This picture includes a man in a bowler hat with an Apple in front of his face. And if one looks closely, you may notice that his left elbow is backwards.

This is one of two artworks of Magritte's where a man with a bowler hat has his face covered by an item (other image is The Man in the Bowler Hat).