What is the scariest thing you’ve ever done? This is the question Chris Hadfield, retired astronaut and inspirational figure, asks in this latest speech from TED Talks. As he relates his rather unique experiences of going into space, commanding a mission aboard the International Space Station, and going blind while on a spacewalk, he addressed the key issue of how to distinguish between fear and danger while doing both great things, or just living our daily lives.

In relating the dangers of going into space, he encapsulates it all with an old astronaut saying: “there is no problem so bad that you can’t make it worse.” That is what fear is, according to Hadfield: an irrational reaction that makes a bad situation worse rather than better. In any situation, knowing the difference between fear of danger and actual danger is key, and can lead to a fundamental shift in one’s thinking that will also have life-changing implications and make some amazing things possible.

Using his characteristic combination of wit, showmanship, and a multimedia presentation, Hadfield demonstrates some of those amazing things. As a fundamentally dangerous profession, many wonder why anyone would risk going into space. According to Chris, the answer is that fear should not prevent us from doing amazing things, witnessing amazing things, and taking part in something that has immense importance and life-changing implications.

And of course, he finishes things off by performing part of his own rousing version of David Bowie’s “Space Oddity” and some sage advice:”Fear not!” Enjoy the video!