Whoever Murphy was, he was a prolific lawmaker. Best known is his First Law ("Whatever can go wrong, will go wrong"), but he didn't stop there.

Murphy's Second Law:

Everything takes longer than you think.

Murphy's Third Law:

Nothing is as easy as it looks.

Murphy's Fourth Law:

If there is a possibility of several things going wrong, the one that will cause the most damage will be the one to go wrong.

Murphy's Fifth Law:

If anything just cannot go wrong, it will anyway.

Murphy's Sixth Law:

If you perceive that there are four possible ways in which a procedure can go wrong and circumvent these, then a fifth way unprepared for, will promptly develop.

Murphy's Seventh Law:

Left to themselves, things tend to go from bad to worse.

(Farnsdick’s Corollary:After things have gone from bad to worse, the cycle will repeat itself)

Murphy's Eighth Law:

If everything seems to be going well, you obviously have overlooked something.

Murphy's Ninth Law:

Nature always sides with the hidden flaw.

Murphy's Tenth Law:

Mother Nature is a bitch.

Murphy's Eleventh Law:

It is possible to make anything foolproof, because fools are so ingenious.