I suppose you think that persons who are as old as your father and myself are always thinking about very grave things, but I know that we are meditating the same old themes that we did when we were ten years old, only we go more gravely about it. – Henry David Thoreau

Some men so dislike the dust kicked up by the generation they belong to, that, being unable to pass, they lag behind it. – Augustus William Hare and Julius Charles Hare, Guesses at Truth, by Two Brothers

From the earliest times the old have rubbed it into the young that they are wiser than they, and before the young had discovered what nonsense this was they were old too, and it profited them to carry on the imposture. – W. Somerset Maugham