Stephen Hawking. (№ 305731)

The most difficult problem which had to face humanity - our aggressive instincts. In the days of the caveman (let's call it the cave person), these instincts were necessary for survival and was printed in our heads at the level of the genetic code that was dictated by Darwinian natural selection. Now, with all those nuclear weapons that we have, we can no longer wait for evolution will rid us of our instincts. I'm afraid we'll have to use genetic engineering.