After the last of 16 mounting screws has been removed from an access cover, it will be discovered that the wrong access cover has been removed.
The true mystery of the world is the visible, not the invisible.
Experience is a good teacher, but she send in terrific bills.
You've achieved success in your field when you don't know whether what you're doing is work or play.
The dead might as well try to speak to the living as the old to the young.
Science is nothing but developed perception, interpreted intent, common sense rounded out and minutely articulated.
To repeat what others have said, requires education; to challenge it, requires brains.