Now that we have deep learning, we know that more layers don't always give better results. Perhaps intelligence and wit is obtained when associations allow our mind to develop neurons that are useful for modeling interesting features. For example, being good at math and having good reasoning skills are very useful features that can be acquired by education and practice. Also we now know that our brain in much more plastic that what was previously believed, for example taxi drivers brains have a bigger spatial area as a result of learning to around big cities. So the question to get better intelligence is how we make child brains develop neural systems related to useful features?, unfortunately teaching chess is not a solution, but perhaps is a step in the right direction, more research is needed.