John Brockman asks experts what we should fret over—and what to let go

PARENTING Relax, says psychologist Aiison Gopnik. Mostly kids are shaped by their genes and peers. Be concerned about poverty or neglect, not about being the perfect parent. Says Brockman: "Kids will be just fine."

VIOLENCE IN FILMS Fictional mayhem isn't worth all the hand-wringing, says English professor Jonathan Gottschall. Proof that it leads to real violence is shaky.

FINDING LOVE Yes, singles, worry a little. According to psychologist David Buss, 'The competition to attract desirable mates is ferocious," so give it your attention.

INTERNET COLLAPSE Big worry, says historian George Dyson, who believes we are not prepared for an inevitable "catastrophic breakdown oft he Internet."

WORRYING lt is itself a worry because it is mentally "corrosive," says psychiatrist Joel Gold, who fears too many people are fretting instead of enjoying life.