Those who study such things differ on its origin, but all of us who have ever experienced Murphy’s Law agree to its truth. It states: “If anything can go wrong, it will.” Its corollary, called Finagle’s Law, adds, “at the worst possible moment.” Murphy and Finagle collaborated to wake Betsy and me at 4:13 this morning with a persistent chirping sound, not unlike the call of a California Towhee or perhaps the sound a male hummingbird makes during a mating dive.

Persistent it was, this chirping, repeating itself loudly every 30 seconds. Try to ignore that. I did try, for about 30 minutes or so. Impossible. With an exasperated sigh, I rolled out of bed, pulled on a pair of pants, slipped into slippers and trudged to the kitchen to deal with the smoke alarm whose battery had chosen that moment to announce its expiration.

Chirp! . . . chirp!. . .  chirp!

Out the back door to fetch the ladder from the shed attached to the carport and grab a screwdriver, just in case. Snow on the ground. Temperature about 33. Struggled the ladder into place beneath the chirping alarm. Pried it open (I did need that screwdriver), extracted the battery, a 9-volt. CHIRP! . . . CHIRP! . . . ! CHIRP! Descended the ladder, headed for the kitchen. Rummaging through the junk drawer yielded batteries of various sizes, shapes and colors, but not a single 9-volt one, which the smoke alarm requires. Murphy again.

Chirp! . . . Chirp! . . . Chirp!

Went to the computer to learn what time the nearest home improvement store opens. Good news: Lowe’s opens at 6 a.m. Now after 5. I dressed to the accompaniment of the incessant chirp, fed the cat, whose pleas for breakfast had joined the chorus, and headed for Lowe’s, driving carefully over black ice, arriving just as doors opened. Found the batteries immediately and spent several minutes roaming the huge store searching for an employee who would accept my payment. Murphy at work. Paint department guy walked me back to the cashiers’ area just as a late-arriving employee burst into the store, peeled out of his coat and checked me out.

I drove home nervously over patches of black ice, and returned to the ladder, struggling for several minutes to install the new battery. CHIRP! . . . CHIRP! . . .  CHIRP! Finally get it right.

Silence was never so sweet.

Now nearly 7. I made coffee and opened the morning papers.

One theory goes that Murphy’s Law is named for Edward Aloysius Murphy Jr. (1918 – 1990) , who was an American aerospace engineer who worked on safety-critical systems and was fond of saying that anything that could go wrong would go wrong. Others insist that Murphy’s Law was born at Edwards Air Force Base in 1949 and was named for Capt. Edward A. Murphy, an engineer working on Air Force Project MX981, designed to see how much sudden deceleration a person can stand in a crash. Whoever claims the title, we who have experienced Murphy can attest to its harsh realities.

This was not the first time Murphy and Finagle had awakened me to remind me that I should have replaced that battery sooner, preferably during the daylight hours. I seem to recall its having happened at least twice before and always in the wee small hours of the morning, thanks to Murphy and Finagle. This time I learned my lesson. I think, but I won’t need to reform my ways right away. The battery’s package states that it’s good for five years.