Drugs dull your senses and your reflexes yet you still feel sharp and alert. Your confidence in your abilities swells out of proportion. Your ego takes over. You see yourself as indestructible, incomparable. That image of yourself may be the last thing you ever see. You don't need an unreal "high" that can mar your judgment. There's no margin of error in this business. A single mistake can cost you your life. A professional needs a clear head and unhampered reflexes at all times so he can react properly to any situation. There's nothing you can do when you're drunk that you can't do when you're sober 10 times better. At the same time, ignorance is bliss, knowledge is painful. Maybe giving yourself brain damage by using drugs isn't such a bad idea.
"The world is just fine the way it is. You're the problem. Not us."