Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

You’ve probably heard that it takes 21 days to form a habit, but if you’ve tried this before and failed, you’re not alone. The truth is, most people get the 21-day rule completely wrong. They think it ...

Small, repeatable improvements powered Clear’s best-selling book and multimillion-dollar business. James Clear didn’t start as the world’s most famous habits expert. In fact, he started as a guy with ...