Safety First

I heard that someone had heard from someone else that the only people who will survive in this world, those who will be favoured by natural selection and the evolution process, are those who are cautious.
The revenge of the ultra-paranoid population. 
It's not impossible.
From experience over the years, I've realized that I'm one of those people. If something goes terribly wrong while doing Task A, I will stop doing Task A altogether and never do it again. I'll sit thinking for hours of the million other things that could have gone wrong, so much that I'm too freaked out to ever think of doing Task A again. 
I can't quite decide if this paranoia is just over-caution or some sort of psychological disturbance. Either way, if thinking about the possible negativities can save your life, then I'm paranoid.
To the rest of you, be careful.