This is the core of my thinking on the matter. How big could life forms like these become? Interesting thoughts require not only a complex brain, but also suff

This is the core of my thinking on the matter. How big could life forms like these become? Interesting thoughts require not only a complex brain, but also sufficient time for formulation. The speed of neural transmissions is about 300 kilometers per hour, implying that the signal crossing time in a human brain is about 1 millisecond. A human lifetime, then, comprises 2 trillion message-crossing times (and each crossing time is effectively amplified by rich, massively parallelized computational structuring). If both our brains and our neurons were 10 times bigger, and our lifespans and neural signaling speeds were unchanged, we’d have 10 times fewer thoughts during our lifetimes. If our brains grew enormously to say, the size of our solar system, and featured speed-of-light signaling, the same number of message crossings would require more than the entire current age of the universe, leaving no time for evolution to work its course. If a brain were as big as our galaxy, the problem would become even more severe. From the moment of its formation, there has been time for only 10,000 or so messages to travel from one side of our galaxy to the other. We can argue, then, that, it is difficult to imagine any life-like entities with complexity rivaling the human brain that occupy scales larger than the stellar size scale. Were they to exist, they wouldn’t yet have had sufficient time to actually do anything. http://nautil.us/issue/51/limits/can-a-living-creature-be-as-big-as-a-galaxy-rp http://nautil.us/issue/51/limits/can-a-living-creature-be-as...