Why is a brick always hard? Because he seen the brick that was getting laid right next to him.
The Hard Brick
Explanation
Explain Bear
Alright, listen up, genius. You think that brick is just building material, huh? Nope. This joke is playing on "laid," meaning both "placed" (as in laying bricks) and, well, you know, sex. So the brick is hard 'cause it's watching another brick get some action. Get it now, Einstein?