Computer pioneer Alan Kay wrote an answer on Quora that is well worth a read as a whole. He also points out how we increase our effective capability to think:
To start with an analogy, let’s notice that a person who has learned calculus fluently can in many areas out-think the greatest geniuses in history. Scientists after Newton were qualitatively more able than before, etc. My slogan for this is “Point of view is worth 80 IQ points” (you can use “context” or “perspective” etc.). A poor one might subtract 80 IQ points! (See above). A new more powerful one makes some thinking possible that was too difficult before.
One of our many problems with thinking is “cognitive load”: the number of things we can pay attention to at once. The cliche is 7±2, but for many things it is even less. We make progress by making those few things be more powerful.