Optimism bias is a cognitive illusion that 80% of us have. We overestimate the likelihood of good events and underestimate the likelihood of the bad events. For instance, on average, we all have 30% of chances to get cancer in our life. Yet, we choose not to think about it. A great example of it was the fact that British government asserted that optimism could increase the length and costs of projects. They actually adjusted the olympics budgets to the optimism bias. In her research, Tali Sharot, a cognitive neuroscientist studies why our brains are biased towards this optimism. Here team discovered that our brains do not respond with the same intensity to good and bad news: when they are good, the neuro-responses are much more intense than when they are bad. It’s a physical reaction: we are biased towards positive information. We think that bad things happen to others, not to us. In a very interesting TED talk, Sharot explains that this bias is not bad: without it we would undoubtedly all be more depressed. Moreover, optimism has a lot of benefits, its leads to success in sports, in politics, and even in health. The truth is that to make any kind of progress, we need to imagine another reality and thus be optimistic.