Wikipedia defines common sense as “knowledge, judgement, and taste which is more or less universal and which is held more or less without reflection or argument”
Try to avoid using this topic to express niche or unpopular opinions (they’re a dime a dozen) but instead consider provable intuitive facts.
Pretty much anything related to statistics and probability. People have gut feelings because our minds are really good at finding patterns, but we’re also really good at making up patterns that don’t exist.
The one people probably have most experience with is the gambler’s fallacy. After losing more than expected, people think they’ll now be more likely to win.
I also like the Monty Hall problem and the birthday problem.
The gambler’s fallacy is pretty easy to get, as is the Monty Hall problem if you restate the question as having 100 doors instead of 3. But for the life of me I don’t think I’ll ever have an intuitive understanding of the birthday problem. That one just boggles my mind constantly.
Lemme try my favorite way to explain the birthday problem without getting too mathy:
If you take 23 people, that’s 253 pairs of people to compare (23 people x22 others to pair them with/2 people per pair). That’s a lot of pairs to check and get only unique answers
Really? The birthday problem is a super simple multiplication, you can do it on paper. The only thing you really need to understand is the inversion of probability (
P(A) = 1 - P(not A)
).The Monty hall problem… I’ve understood it at times, but every time I come back to it I have to figure it out again, usually with help. That shit is unintuitive.
The birthday problem is super easy to understand with puzzles! For example, how does laying out the edges increase the likelihood of a random piece to fit.
One of my favourite pages on wikipedia:
https://en.wikipedia.org/wiki/List_of_cognitive_biases
The thing about that is that it’s a little too complete. How can there be both negativity bias and normalcy bias, for example?
To make any sense, you’d need to break it down into a flowchart or algorithm of some kind, that predicts the skew from objectivity based on the situation and personality tendencies.
I think they probably appear in different types of situations, not all at once. And maybe different types of people/thinking are more prone to some than to others.
Related to gambling: being “pot committed”
Pot committed is more a math reality with a small amount of sunk cost fallacy. There’s always a non zero chance someone is bluffing. A 99% chance to lose $11 is better than a 100% chance to lose $10 if you can win $100 on that 1%.