Occam's razor
Not a bias
A problem-solving principle that says, among competing explanations, the one with the fewest assumptions should usually be preferred. It is a useful rule of thumb, but leaning on it too hard leads us to favor a simple explanation even when the evidence points to a more complex one.
In everyday life
A company blames falling sales on one new competitor and ignores several smaller causes that together explain the drop better.
Your houseplant is wilting and you decide it just needs more water, ignoring that it also sits in a cold draft and its roots have outgrown the pot.
Why your mind does this
Simple, clear options are faster to understand and easier to act on, and when time is short that speed matters. Known odds and complete information feel safer because they let us predict what will happen. Preferring the clear option often saves effort that would be wasted on puzzles we can't solve.
Its family, in 30 seconds: Simple & complete
How to spot it
Ask whether your explanation accounts for all the facts, or only the ones that fit neatly.
What you can do
List every fact that needs explaining and check that your chosen explanation covers each one.
Same family: Simple & complete
SourcesLombrozo (2007)·Wikipedia