More broadly, it seems plausible to say that a smarter overall population would increase humanity’s ability to solve a wide range of global problems. Consider Bostrom’s calculation that a 1 percent gain in “all-round cognitive performance … would hardly be noticeable in a single individual. But if the 10 million scientists in the world all benefited … [it] would increase the rate of scientific progress by roughly the same amount as adding 100,000 new scientists.” Although I noted above that accelerating the pace of science could have disadvantages, it might also put humanity in a better position to neutralize a number of existential risks. For example, superior knowledge about supervolcanoes, infectious diseases, asteroids, comets, climate change, biodiversity loss, particle physics, geoengineering, emerging technologies, and agential risks could lead to improved responses to these threats.
Radical enhancements could also expand our cognitive space, potentially allowing us to acquire knowledge about dangerous phenomena in the universe that unenhanced humans could never know about, in principle. In other words, there could be any number of existential risks looming in the cosmic shadows to which we, stuck in our Platonic cave, are cognitively closed. Perhaps we are in great danger right now, but we can only know this if we understand a Theory T. The problem is that understanding Theory T requires us to grasp a single Concept C that falls outside our cognitive space. Only after we recognize a risk can we invent strategies for avoiding it.