Stephen Hawking has expressed concern that if aliens discover us, it may be catastrophic for the future of human beings. Hence, we’d better to hide ourselves from discovery.
Neil deGrasse Tyson does not share this concern. He says the basis of this pessimism is the behavior and violence of human beings when meeting other living beings of lower level of sophistication. There is no reason that all life form are like humans.
The video also contains very interesting ideas about interplanetary travel, terraforming Mars, and the like.
