Use Your Imagination

The origination of Murphy's Law ("Anything that can go wrong, will") is
usually attributed Edward A. Murphy Jr., an engineer working at rocket sled
tests at Edward's Air Force Base between 1948 and 1950. However, Fred
Shapiro, editor of the Yale Book of Quotations, has located a much earlier
source: none other than magic's own Nevil Maskelyne. 

In 1908, Maskelyne wrote in The Magic Circular: 

"It is an experience common to all men to find that, on any special
occasion, such as the production of a magical effect for the first time in
public, everything that can go wrong will go wrong. Whether we must
attribute this to the malignity of matter or to the total depravity of
inanimate things, whether the exciting cause is hurry, worry, or what not,
the fact remains." 

Again according to Shapiro, this proverb appeared in more than one
publication (including one in 1928), so apparently it was well known amongst
magicians of the era. However, the earliest known instance of what became
this proverb was found in the 1877-78 minutes of the Institution of Civil
Engineers, in which Alfred Holt is quoted as saying "It is found that
anything that can go wrong at sea generally does go wrong sooner or later."
Still, it seems that magic got it first to print, so we really should call
this "Maskelyne's Law."