I think that.....'And in the end the love you take is equal to the love you make'.....is pretty good.
Also, the guru figure at the end of The Monkees' film 'Head' (made in '68) came out with:
'The tragedy of your generation, my young friends, is that you may get exactly what you want.'
How prescient is that?
To give just one example the legalization of pot (or certainly the acceptance of its casual use) has resulted in a whole lot of glazed-looking consumers as far as I can see. Just watch one episode of the 'Jeremy Kyle Show' for the evidence!