Tag Archives: William of Ockham

7. How to Think Like a Scientist – Shaving the Truth with Occam’s Razor

William of Ockham (c. 1287 – 1347) was an English Franciscan friar and scholastic philosopher and theologian, who is believed to have been born in Ockham, a small village in Surrey. (William of Ockham, from stained glass window at a church in Surrey.)
William of Ockham (c. 1287 – 1347) was an English Franciscan friar and scholastic philosopher and theologian, who is believed to have been born in Ockham, a small village in Surrey. (William of Ockham, from stained glass window at a church in Surrey.)

As Mac would say, I’m a freakazoid.  I don’t put milk in my cereal.  Never.  But I love a cold glass of milk with my cereal. So having finished off the gallon last night with dessert, I was keenly aware that we were out of milk, and that this morning was going to start off badly.

Instead, when I awoke I was pleasantly surprised and a bit shocked to find a fresh gallon sitting in the fridge!  Where did it come from?  My pre-breakfast mind quickly came up with three possible answers to the presence of the mysterious milk jug.

  1. My wife got up early and picked up some groceries before going to work.  or…
  2. Burglars broke into my house and left behind a gallon of milk.  or…
  3. My wife bought a cow last night, stabled it in the garage, and milked the cow this morning.

Of course there are many more possible answers.  But these were my top three pre-breakfast guesses and all successfully explained the mystery milk.

Before doing any investigation, how do I choose?  Which answer should I prefer?  Talking like a scientist, “which one would be my working hypothesis?”  Fortunately science has a great tool to help.  It’s called Occam’s Razor.

Occam’s Razor is named after 14th century philosopher, William of Ockham, who argued that “simpler explanations are, other things being equal, generally better than more complex ones.”

razorHis razor blade shaves away details that are unnecessary.

Very often in science (and in life), there is more than one solution that can explain a mystery.  Occam’s Razor picks the simplest solution, until there is a need for more accuracy.  The principle allows you to quickly decide where to focus your efforts.

In my case, scenario 1 is the simplest answer.  My wife bought some milk this morning.  This may be wrong.  But until I hear mooing coming from the garage, or see a newspaper headline about “Burglar Bandits Leave Milk Behind”, this is my working hypothesis.

Your math teacher would use the Razor if a student claimed that space zombies stole his homework.  Occam’s Razor would suggest that maybe the student just forgot to do the assignment.

Remember, Occam’s Razor is a guide. not a judge.  Start simple, and only add complications when you need to explain additional observations.  It may turn out that space zombies did steal the kid’s homework.   And I may have a cow in my garage.  I’ll go check after breakfast.


Illustration Credit: Razor detail from linen texture postcard, Boston Public Library. “Since 1731, J.A. Henckels Twin Brand Razors and Shears, radiant with quality and beauty like the rising sun, have been recognized by the discriminating master barbers as the best the world produces and the most satisfactory and the most economical to use.” Harry H. Baumann, 216 W. 18th Street, New York.1930 – 1945 (approximate)