Chisholm Effect: Basic laws of frustration, mishap, and delay
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1st law of human interaction. If anything can go wrong, it will. 2nd law. When things are going well, something will go wrong. 3rd law. Purposes, as understood by the purposer, will be judged otherwise by others. Corollary: If anything just can't go wrong, it will anyway.
Corollary: When things just can't get any worse, they will.
Corollary 2: Anytime things appear to be going better, you have overlooked something.
Corollary: If you explain so clearly that nobody can misunderstand, somebody will.
Corollary 2: If you do something which you are sure will meet with everybody's approval, somebody won't like it.
Corollary 3: Procedures devised to implement the purpose won't quite work.