Many of the greatest errors in asset management stem from cultural and structural pressures to do the wrong things at the wrong times, from wrong-headed conventional wisdom, and from unexamined acceptance of theory as fact. We need to remember that neither people nor companies can earn returns on money they haven’t first set aside for investment; we need to question why each $1 in stocks is not considered to be worth the same as $1 in bonds; and we need, always, to test our assumptions.