> that also means that it's unlikely that significant evolutionary pressures went into designing the complex systems responsible for intelligent thought, so the

> that also means that it's unlikely that significant evolutionary pressures went into designing the complex systems responsible for intelligent thought, so they were probably accidentally "designed" via random drift I find this unlikely. Perhaps the initial "push" towards intelligence was based in random drift, but humans' evolutionary path has actually paid quite a dear price to have the high intelligence that we have: * Larger brains led to larger heads * Larger heads led to the need to give birth earlier, and with more risk * Earlier birth lead to helpless babies * Helpless babies require much more care, and mothers become dependent on fathers * Large brains are only very useful if trained for long periods of time leading to long, expensive and dangerous childhoods I don't think this whole process can be explained by random drift. I think the question of what caused pressure towards higher intelligence in our evolutionary process can be answered by competition. Analogously, consider tree heights. A tree doesn't need to be very high at all to collect sunlight. But a tree competing with other trees can grow to tremendous heights due to competition. When competing for resources with other similarly intelligent beings, more intelligence could definitely yield an evolutionary edge.