Is There Some Extraterrestrial Life Out There?

Scientist: For most of my life, I have thought that there's just got to be something out there. But as I've learned more and worked on articles like this, they're a little more hesitant. Life arose here from physics and chemistry, became biology. And we don't actually know how hard it is. We don't know how likely it is. So my new stance is that I don't know and I'm not making any guesses.