All political thinking for years past has been vitiated in the same way. People can foresee the future only when it coincides with their own wishes and the most grossly obvious facts can be ignored when they are unwelcome.
Educate your children to self-control, to the habit of holding passion and prejudice and evil tendencies subject to an upright and reasoning will, and you have done much to abolish misery from their future and crimes from society.