well, my guest today is the san francisco tech billionaire, dave friedberg. he says science and technology can and will fix humanity's problems. should we believe him? dave friedberg, in san francisco, welcome to hardtalk. yeah, thanks for... thanks for coming by. it's a real pleasure to be here. you describe yourself as an "extreme optimist" when it comes to we humans and our ability to overcome the most fundamental challenges we face. yeah. what do you base that optimism on? well, i think history's a good predictor. so historically, humans have... ..found themselves facing existential threat, right, it started when we were roaming the savannah looking for food, and then, we realised we could engineer the earth and make food. and that was the dawn of agriculture. and every time humans have faced some sort of existential threat, and it has been many times in our history — and we always seem to think we are facing an existential threat, perhaps we're hard—wired evolutionarily to think that — our ingenuity always seems to prevail. some new invention or engineer

well, my guest today is the san francisco tech billionaire, dave friedberg.