The 'illusion of knowledge' that makes people overconfident

If you consider yourself reasonably intelligent and educated, you might assume that you have a fair grasp on the core ways the world works - knowledge about the familiar inventions and natural phenomena that surround us. However, it's quite likely you know less than you think.

 This bias is known as an “illusion of knowledge”. This can afflict our judgment in many domains. In the workplace, for example, it can lead us to overclaim our knowledge in an interview, overlook the contributions of our colleagues and take on jobs we may be wholly unable to perform.

Many of us overestimate how much we can learn by observing others - resulting in the illusion of skill acquisition.

Passive observation can even increase people's confidence in their abilities to perform complex life-or-death tasks. For example, one study found that people thought they would score a greater number of points if they watched a video 20 times compared to watching it once. But their actual performance did not show any evidence of learning.