If you had to sum up what education's main principle should be in one sentence, how would you do it?

In America, it has changed to liberal indoctrination.

It's to inform while simultaneously encouraging independent thought.

Teach how to learn. Instill a life-long passion for learning. Anyone who thinks "I graduated, learning is over" is a fool.

Dear Parent- I am writing to advise you that i have taken steps to stop the political bullshit, tearing down landmarks that people find offensive. I will be instructing the education department that any teachers who are offended by this letter i will be accepting their resignation as soon as possible. Finally I will instruct the education department being politically correct has now been abolished - Thanks Ned Kelly Education Minister

I could do in one word. Indoctrination!

Teaching people how to think.

apparently some people can't read...I think the question said "should be". Everyone who said indoctrination must live in a Maoist society..

Teach people how to research facts, study and reason through thinking.

'Learning is a matter of discovery'...

Enlightenment.