Astronaut Chris Hadfield has a dangerous job. When he took his first shuttle flight in 1995, the odds of a catastrophic event taking place was 1 in 38. The math alone would terrify some people, but Hadfield wasn’t afraid. Why?

Passion didn’t quash his fear. Sure, he’d dreamed of going to space since he was a young boy, but that wasn’t enough to override his fight-or-flight instinct. Instead, it was a shift in mindset – coupled with extensive preparation – that helped take his perception to another place and allowed him to live his dream.

In his TED Talk, Hadfield explains how his extensive training – which saw him practice things going right and spend even more time practicing things going wrong – made him realize a potentially scary scenario wasn’t really that scary after all.

“You have taken the dreams of that nine-year-old boy, which were impossible and dauntingly scary, dauntingly terrifying, and put them into practice, and figured out a way to reprogram yourself, to change your primal fear so that it allowed you to come back with a set of experiences and a level of inspiration for other people that never could have been possible otherwise,” says Hadfield.

It’s also important to recognize the role others have in planting the seed of fear in our minds. Naysayers come in many forms, including spouses, family members, friends, business acquaintances and advisors. It goes beyond constructive criticism or playing devil’s advocate – naysayers are pessimists who leap at the opportunity to scold and discourage you from trying new things.

While seeking input from others is important, a naysayer’s opinion should never be the primary decision-making criterion. After all, if these killjoys had their way, our society wouldn’t be where it is today. All the progressive, perceived-as-risky moves that drive innovation would have been shut down before they got off the ground. We’re sure Hadfield encountered a naysayer or 12 in his time, all who likely tried to convince him becoming an astronaut was an unrealistic goal, or too dangerous an occupation for a family man.

In the case of Hadfield, the statistics showed real risk associated with his job. More often, the things we fear pose very little danger even if our brains try to tell us otherwise. Learning how to identify true danger and work through our irrational fears can open doors to us that we never thought possible. We all should be able to make decisions without fear being our primary effecter.

So what would you do if you weren’t afraid? Don’t let your fear hold you back. Check out Hadfield’s TED Talk to learn more.