> the raw processing power achievable by your brainBut "achievable" is not the same as "achieved". To actually achieve the full raw processing power that your brain is capable of achieving, you have to work at it--not just in terms of developing skills, but in terms of realizing the processing power. Your brain is not like a computer with a fixed amount of CPU and memory that you just have to load with software. If you don't exercise it, it doesn't develop; exercising it doesn't just make you more skilful at using the processing power you have, it actually increases the processing power. Yes, there's a limit imposed by your genetic makeup as to how much exercise can increase the processing power; but no child is going to be anywhere near that limit, simply because the child is still growing and developing. (I would argue that most adults aren't really at the limit either, any more than most adults are at the limit for any capability. Few people have the genetic makeup to run a 100-meter dash in under 10 seconds; but how many people can run a 100-meter dash in the shortest possible time for their genetic makeup, whatever that time is?)
In other words, while there is a concept of "raw processing power achievable", I don't think it's a very useful concept by itself, because people can't help jumping from "the maximum raw processing power you can ever achieve is genetically fixed" to "the actual processing power you have right now is genetically fixed", and the latter is not only false, it's pernicious, because it creates the worst possible mindset.