And then there are many corollaries to his law:
Murphy's Original Law If there are two or more ways to do something, and one of those ways can result in a catastrophe, then someone will do it.
Murphy's Law If anything can go wrong -- it will.
Murphy's First Corollary Left to themselves, things tend to go from bad to worse.
Murphy's Second Corollary It is impossible to make anything foolproof because fools are so ingenious.
Quantized Revision of Murphy's Law Everything goes wrong all at once.
Murphy's Constant Matter will be damaged in direct proportion to its value.
The Murphy Philosophy Smile... tomorrow will be worse.
Father Z has posted his own modern version of the law on how it applies to computers.
Murphy was an optimist.
Corollary 1: When you need your technology to work, that is when it will fail.
Corollary 2: The extent of the failure is proportioned to the urgency of the need.
Corollary 3: When you want to show someone the great gizmo or program you have, that is when it won’t work.
Corollary 4: When the person to whom you wanted to show off your great gizmo or program departs, unimpressed, that is when it will once again begin to function properly.
From Father Z: