Steven Hawking on the Evolution of Intelligence

Intelligence, Hawking believes contrary to our human-centric existence, may not have any long-term survival value. In comparison the microbial world will live on, even if all other life on Earth is wiped out by our actions. Hawking's main insight is that intelligence was an unlikely development for life on Earth, from the chronology of evolution: "It took a very long time, two and a half billion years, to go from single cells to multi-cell beings, which are a necessary precursor to intelligence. This is a good fraction of the total time available, before the Sun blows up. So it would be consistent with the hypothesis, that the probability for life to develop intelligence, is low. In this case, we might expect to find many other life forms in the galaxy, but we are unlikely to find intelligent life."

link: Stephen Hawking: Why Isn't the Milky Way "Crawling With Self-Designing Mechanical or Biological Life?"