intelligence := ability to build models [only exists relative to $domain, but training the brain to perform well in one domain translates to enhanced capability

intelligence := ability to build models [only exists relative to $domain, but training the brain to perform well in one domain translates to enhanced capability in others; see link between iq and affinity to music etc.]. the speed of cognition is basically a symptom of how well your brain is trained to perform a task in some domain; someone deeply versed in theoretical physics, doing objectively hard mathematical work in his daily life, may be very slow at other cognitive tasks, if the neuro-pathways of the different tasks/domains are not aligned. It's complicated, mashing the entire concept of "cognitive ability" into a single, one-dimensional term is not really doing the topic justice. We're just used to it, because groups need to converge on the simplest, most accessible abstraction of the idea (of cognitive ability, in this case). Truth is, "intelligence" as a broad term doesn't make that much sense.