April 29, 2020–In the Time of the Virus, I’ve been going through my bookshelf to find inspiration and ideas. Among the editions not yet donated to the library book sale, I came across an old favorite from 1983–Rules of Thumb, by Tom Parker.

He defined a Rule of Thumb as a homemade recipe for making a guess. It’s not always right. But it is a personal tool for making things work most of the time. We all know a few:

  • The literal “rule of thumb” that the first joint of your thumb measures one inch.
  • When spaghetti is done, it will stick to the wall.
  • When tuning a stringed instrument, it is less apt to slip out of pitch if the strings are tuned up from flat.

Back in the days when all the world’s knowledge had yet to migrate to the anthill we call the web, Parker sent out postcards from a fictional organization to everyone he could think of, asking for Rules of Thumb. So many responses came back he compiled a book. Many are profound. Many are helpful. Many are useless, yet fascinating–like celebrities who post online.

Here are a few of my favorites from the book…

  • Eating Cheese: The quality of the flavor of cheese is inversely proportional to the thickness of the slice.
  • Planning A Dinner: Inviting more than 25 percent of the guests for a university dinner party from the economics department ruins the conversation.
  • Catching Crabs in Texas: Crabbing season in Texas consists of all the months with the letter R in them. You can catch crabs during the other months but they aren’t good to eat.
  • Calling In Sick: In half of all cases, when an employee calls in sick, he’s actually sick.
  • Testing an Edge: Any cutting edge that reflects light is in need of sharpening.
  • Giving Your Age: Odd-numbered ages seem older than even-numbered ages.
  • Recognizing The Obvious: Clients will recognize the obvious much sooner than professionals.
  • Getting Rid of Stuff: Three moves equal one house fire.
  • Not Wearing Pants: On a cold day wet jeans will draw heat from your lower body twice as fast as wearing no pants at all.
  • The Restaurant Rule of Three: The third restaurant to go into a space is the one that succeeds.
  • Using Dynamite: Wait at least one hour before investigating a charge of dynamite that didn’t go off.
  • Following Ants: Food that ants like to eat is food that people should avoid–sweets, deep-fried items, chips…

Reading these, you can’t resist tossing out your own versions. I came up with a couple based on our current situation:

  • Using a Dishwasher: If the dishwasher is more than half full, run the cycle. If you wait to fill it up, there will be too many dishes for one load.
  • Buying Groceries: When you have one left of any commodity–butter, laundry detergent, toilet paper–buy two more. You will always use them–that’s why they are called commodities.
  • Pleasing Clients: If you do exactly what your client asks, they will be unhappy with the results.


  • Writing A Final Sentence: When writing, if you’re searching for a final sentence, you’ve probably already written it.