The writer must be a perpetual dissident, a professional heretic.

Financial regulation must keep up with market changes but avoid excessive intervention.

"Art is the only thing that can save us from the emptiness of existence."

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.