Will Wilkinson blogs about politics for The Economist and about the science and politics of human nature for Forbes. He lives in Iowa City, Iowa.

Bad Math

The bestselling Positivity tells us that there’s a precise tipping point at which being chipper delivers health and success, a conclusion trashed by a new study. Will Wilkinson sorts out the controversy.

In his budget speech, the president called on the nation to share sacrifice, but only the rich are being called upon to bear that burden—his $4 billion deficit reduction depends on touchingly optimistic savings from Obamacare, not cuts to entitlements.