"Every city has its own secret rhythm, and those who listen can hear its stories."

A man, as a general rule, owes very little to what he is born with – a man is what he makes of himself.

So given a Time Turner, I would tell my 21-year-old self that personal happiness lies in knowing that life is not a check-list of acquisition or achievement. Your qualifications, your CV, are not your life, though you will meet many people of my age and older who confuse the two. Life is difficult, and complicated, and beyond anyone’s total control, and the humility to know that will enable you to survive its vicissitudes.

Memory was in this respect similar to anticipation: an instrument of simplification and selection.