[EdwardDiego]

Your definitions are very interesting there mate. In some contexts, yep, what's often called a rule of thumb (for example, sparkies use a multitude of <X>-hand rules[0][1] and call them rule of thumb, because you know, there's a thumb involved) are passed down.

But people are entirely able to derive their own rules of thumbs, if we hark to the common definition that a rule of thumb is a principle/procedure/process derived from practical experience.

For example, I rapidly developed a rule of thumb when dating post-divorce that any person who said "I hate drama" in their dating profile is in actual fact the source of any drama, but it took me a couple of disastrous dating attempts to develop that rule of thumb.

[0]: https://en.wikipedia.org/wiki/Right-hand_rule#Electromagneti...

[1]: https://en.wikipedia.org/wiki/Fleming%27s_left-hand_rule_for...