Law of Parsimony

Definition of Law of Parsimony

The Law of Parsimony, also called Occam’s Razor, tells us that the easiest explanation is often the best one. That means when there’s something we don’t understand and there are many ways to explain it, we should start with the explanation that doesn’t twist our brain into knots trying to make sense of it. This helps to clear up the noise and make sure we’re not making things more complicated than they need to be. It’s like picking the shortest, straightest path to walk through a park, rather than a zigzagging one that takes twice as long.

How to guide: To use the Law of Parsimony, here’s what you do:

  1. Look at all the different ways you can explain something.
  2. Think about how much you have to assume or guess to believe each explanation.
  3. Lean towards the one that doesn’t make you guess too much—it’s probably closer to the truth.
  4. Lastly, compare that simple answer to what you know for sure to check if it still makes sense.

Examples of Law of Parsimony

  • If you’re outside and you hear hoof sounds, the Law of Parsimony suggests you expect a horse, not a zebra. Since horses are common in many places and zebras aren’t, guessing horse involves fewer assumptions.
  • When something electronic stops working, a repair person will first check simple stuff like if the power cable is plugged in or if the battery’s dead. This is because these issues require fewer assumptions and are more common than the device having a complicated internal problem.
  • If a classroom is messy, the Law of Parsimony might suggest that the students made the mess, rather than a sudden indoor tornado. A mess made by students doesn’t need as many assumptions, like how a tornado got in the room in the first place.
  • When hearing a story, if it sounds far-fetched or like it’s out of a movie, the Law of Parsimony will have you consider if the storyteller might be exaggerating. It’s simpler to assume someone is stretching the truth than believing in an elaborate, unusual event.
  • In sports, if a soccer team usually wins because of its strong defense, then it’s reasonable to think they won their latest game for the same reason. It would be more complicated to assume they suddenly changed their strategy.

Why is it important?

The Law of Parsimony stops us from chasing our tails by overthinking. In science, having clean and practical theories means we can better understand the universe without getting lost in wild guesses. Think about it this way: when you clean your room, it’s faster and easier when everything has a place. If you started guessing where things might go without any reason, you’d never finish. This principle matters in our daily lives too because it helps us solve problems quicker and saves us the headache of wondering about a million “what ifs.”

Implications and Applications

The Law of Parsimony can affect a lot of different fields, like these:

  • Science: When scientists have a few ideas about how something in nature works, they often go with the simpler idea. This is because it’s easier to check if they’re right and it tends to make more sense when you look at the whole picture.
  • Philosophy: Philosophers like to keep their arguments solid but not too tangled. Using parsimony means they try to make their point without too much fluff that doesn’t help get to the heart of the matter.
  • Everyday Life: We all face choices and puzzles in life. Using Occam’s Razor can help us find answers faster and not get stuck when things seem too tough to figure out.

Comparison with Related Axioms

The Law of Parsimony has buddies in the world of ideas that also love simplicity, like ‘less is more’. They all value keeping things uncluttered, but Occam’s Razor is special because it’s all about deciding which explanation for something is the best.


This idea got its name from a guy named William of Ockham who lived in the 1300s, even though he wasn’t the first to think of it. Even the old Greek philosopher Aristotle had the idea that the simplest way is often the best way.


Not everyone is a fan of the Law of Parsimony. Some people say the world is complex and the simplest answer isn’t always right. There’s debate, especially in science, about how much we should rely on it when we’re figuring out what’s true.

Related Topics

  • Simplicity Theory: This is all about finding the simplest ways things can work. The Law of Parsimony fits right in because it looks for the simplest explanations.
  • Minimalism: Minimalism isn’t just about having less stuff – in ideas, it means not going overboard with explanations. Again, it links back to the Law of Parsimony, as it favors the less complicated reasoning.
  • Heuristic: Heuristics are like shortcuts for thinking. The Law of Parsimony can be seen as a mental shortcut to avoid overcomplicating our thoughts when we’re trying to understand why things happen.


The Law of Parsimony, or Occam’s Razor, is a way of thinking that helps save time and energy by stopping us from looking for complicated answers when simple ones will do. It’s useful in science, philosophy, and just living day-to-day. Even though it’s not perfect and can cause debates, as long as we’re careful with how we use it, this principle can be a really handy tool for sorting through life’s puzzles and keeping our thoughts as simple and clear as possible.