There is general agreement among psychologists that intelligence is composed of two components: fluid intelligence and crystallized intelligence. Fluid intelligence is related to neural efficiency, manifest in the ability to learn quickly, solve problems, comprehend abstract ideas, and retain information in short-term memory long enough to make connections. The more efficiently the brain is “hard-wired” in its neural connections, the greater the fluid intelligence. Neurologists are exploring different brain structures using new brain scanning technologies to ascertain which neural structures correspond to greater fluid intelligence, but these studies are still in their infancy. However, it is generally believed that a person’s fluid intelligence is mainly determined by the genes they inherit.
Crystallized intelligence, on the other hand, represents the accumulated experience and knowledge that underpins comprehension and judgement–cognitive abilities that grow and mature over time. As Aristotle observed over 2300 years ago:
Although the young may be experts in geometry and mathematics and similar branches of knowledge, we do not consider that a young man can have prudence. The reason is that prudence includes a knowledge of particular facts, and this is derived from experience, which a young man does not possess; for experience is the fruit of years.
Crystallized intelligence depends largely on environmental factors such as a person’s home environment, education (whether formal or informal) and career. A person who grows up in a home where learning is valued, where ideas are discussed, and where free-thinking is encouraged has a huge intellectual head start relative to those who come from homes bereft of intellectual interest. Of course you have no control over your genes or the home environment in which you spent your early years, so your efforts to increase your IQ should be aimed at increasing your crystallized intelligence, i.e., expanding the depth and scope of your cerebral experiences. To achieve this, I suggest the following:
• Read extensively across a broad range of the humanities, selecting from the great classics in philosophy, history and economics. This is arguably, the easiest to achieve.
• Study mathematics until you are sufficiently fluent in areas like statistics to understand how to interpret and analyze data. As you study deductive proofs, you will learn how to build a logical argument from basic assumptions or axioms. Abraham Lincoln structured his speeches to emulate Euclidean proofs. The study of mathematics will increase your ability to think in the abstract, and the training in logical structure will help you if you wish to learn a programming language.
• Learn as much science as possible, from biology to physics. You can learn the essential ideas of Relativity Theory and quantum physics, even if you do not understand the mathematics underpinning these disciplines. Quantum physics, in particular, addresses some of the deepest questions in classical philosophy, such as determinism and perception.
The great mathematician and physicist, Henri Poincaré, asserted in 1908, that when we are resting, our brain is “unconsciously” working on a problem that we addressed while conscious. Since then, many scientists, including Jonas Salk who developed the polio vaccine, have attested to this neural activity. (See: What are some good science books that, though not about human intelligence as measured by IQ per se, are based on information derived therefrom? – Intelligence and IQ )
Much of our neural development occurs after conscious cerebral effort during a period of incubation. When I was a student, I sometimes encountered ideas that were difficult for me to understand, yet a few months later, I found that they seemed simple and I couldn’t recall what it was that I had found difficult. It seems that every time we stimulate our brain by learning something new or working on a problem, we are re-wiring our brain incrementally, and all these increments eventually change who we are. Enjoy building your IQ, it will bring you significant benefits.
