Things eveyone should know and other people already said better...

We cannot learn without pain - Aristotle

Anyone who has never made a mistake has never tired anything new - Albert Einstein (It's always good to try new things, right, Gran?)

Leadership and learning are indispensable to each other - JFK

Education is not received; it is achieved - Unknown

Confidence comes not from always being right, but from not fearing to be wrong - Peter T. McIntyre

It is not easy to find happiness in ourselves and it is not possible to find it elsewhere - Agnes Repplier

The life given us by nature is short, but the memory of a life well spent is eternal - Cicero