Most people are hard-wired to expect a rosier future than the odds support

Across ages, cultures and income levels, people systematically overestimate their odds of good outcomes (a long marriage, career success) and underestimate their odds of bad ones (divorce, illness). Neuroscientist Tali Sharot traced this optimism bias to how the brain updates beliefs — readily absorbing good news about the future while discounting bad news. The bias persists even after people are shown the real statistics.

— Tali Sharot, The Optimism Bias: A Tour of the Irrationally Positive Brain — Pantheon Books, 2011
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