India, July 19 -- * Too much of anything.

* Don't count your chickens.

* A stitch in time.

* The grass is always greener.

* Money doesn't make the world go round.

The wisdom of the ages is so dinned into us, we now think of it as cliched. Yet these hard-won lessons have shaped people and societies, helping us navigate a shifting world and our changing roles within it.

What is wisdom? Literally, it is a state of knowing (from the Proto-Germanic wis, meaning "to see" or "to know", and the suffix -dom, denoting a state or condition). As Socrates put it, in the 5th century BCE, it is also crucially the state of knowing what one doesn't know.

As for what makes a person wise, this is where it gets interesting.

A large-scale study conduc...