The closest I can find to that quote is the following, from the section called "Dead Programs Tell no Lies": "when your code discovers that something that was

The closest I can find to that quote is the following, from the section called "Dead Programs Tell no Lies": "when your code discovers that something that was supposed to be impossible just happened, your program is no longer viable. Anything it does from this point forward becomes suspect, so terminate it as soon as possible. A dead program normally does a lot less damage than a crippled one."