The unconscious mind is amazing. It can process vastly more information than our conscious mind by using shortcuts based on our background, cultural environment and personal experiences to make almost instantaneous decisions about everything around us. The snag is, it's wrong quite a lot of the time, especially on matters that need rational thinking. Here's a classic example. A bat and a ball cost £1.10. If the bat costs £1 more than the ball, how much does the ball cost? Most people, including over 50% of students at some of the world's leading universities, get the answer wrong and say £10. The answer is actually £5. Many of us choose £10 without thinking. This is because our unconscious mind uses instinct, not analysis. So our unconscious is fallible. It's also biased. It makes snap judgments of people we meet, categorising them according to gender, social and other characteristics. In milliseconds, we judge whether somebody is like us and belongs to our in-group. These are the people we favour. So men might favour men while women might favour women, however we can belong to different in-groups and we like to be part of an in-group that's powerful, which could mean a woman favouring a man over a woman. That's unconscious bias. All of us have it and it colours our decisions without our realising. For example, research reveals that if I were a man, you would be more likely to be nodding in agreement right now because people pay more attention to a male voice. The Royal Society fosters excellence in science, but this can only be achieved if we select from the widest range of talent and that's not possible if unconscious bias is narrowing down the field for non-scientific reasons. To lessen the impact of unconscious bias, which is easier for us to notice in others, we are raising the awareness of unconscious bias to members of our selection and appointment panels. We're encouraging panel members to deliberately slow down decision making, reconsider reasons for decisions, question cultural stereotypes and monitor each other for unconscious bias. We can't cure unconscious bias, but with self-awareness we can address it.