No one likes to talk about IQ because it is inherently divisive, although it does not need be so. There are good people at every IQ level. However, generally speaking, the dumber something is the less coherent its thinking is, bringing it closer to insanity and incompetence.
If the lower IQ person restrains himself to an area which does not require much intelligence, while simultaneously acquiring some control over his appetites and desires, he may end up perfectly functional at that level, but no higher.
All of nature is a hierarchy of consciousness. Those with more of it are able to create and renew, where those with less are able to follow the steps of others and memorize rules and procedures. Each IQ level has its own set of roles in a healthy society.
Lower IQ people also suffer more from self-delusion, not because they are better at it — higher IQ people are — but because they cannot think their way out of it. Higher IQ people tend to be more analytical and creative, therefore think their way out of it.
Most modern people fall below the 115 IQ point mark, but the danger zone is between 115-125 IQ points, where people are perpetual sophomores: smart enough to understand part but not all of complex systems, and not smart enough to think themselves out of seductive illusions like peer pressure.
Interestingly, a good number of the more intelligent have an inner voice which is not like schizophrenic hearing of voices, but the formation of speech to communicate more effectively with themselves:
He observed that elicited inner speaking caused a decrease in activation of Heschl’s gyrus, in
accord with prior elicited-inner-speech research and with some understandings of external
speech, which hold that when we talk, there is a reduction in sensitivity to our own speech
sounds . External speaking is often associated with the dampening of neural responses to
expected sounds in auditory cortex [37, 38], and similar effects are evident during silent articu-
lation , suggesting that articulatory processes are sufficient to induce auditory suppression
even in the absence of external speech. Similarly, in the silent-speech case, it may be that elic-
ited inner speech involves a sufficient level of articulation—albeit silent—to inhibit responses
in Heschl’s gyrus.
By contrast, we found that spontaneous inner speaking was associated with an increase in
Heschl’s gyrus activation. That is the more surprising because inner speaking is phenomeno-
logically speaking, not hearing . One interpretation of these results is that perhaps Heschl’s
gyrus is more involved in representing speech than is usually credited. Though more com-
monly linked with non-verbal auditory imagery , Heschl’s gyrus activation is also evident
during silent lip-reading  and in some cases of auditory verbal hallucinations .
Like hallucinations, this inner voice consists of surging creativity trying to make sense of the world around them. This bears relationship to what was once called “woolgathering,” or idle thought like sketching doodles and notes on a pad, or daydreaming.
Interestingly, this shows that the brain is not straining to hear; rather, it is striving to create a sensible narrative of what sees before itself, using words so that it can be memorized and recalled quickly.
The inner voice builds our mental map of the world around us. It also helps us simplify what we are perceiving and convert it into knowledge, although half to three-quarters of the population do not have this voice. Most rely instead on stimulus response.
The inner voice works to condense the outpouring of stimulus, perception, and creativity into a single coherent narrative:
Our data support the hypothesis that expanded inner speech recruits speech production processes down to articulatory planning, resulting in a predicted signal, the inner voice, with auditory qualities. Along dialogality, covertly using an avatar’s voice resulted in the activation of right hemisphere homologs of the regions involved in internal own-voice soliloquy and in reduced cerebellar activation, consistent with internal model adaptation. Switching from first-person to third-person perspective resulted in activations in precuneus and parietal lobules. Along intentionality, compared with intentional inner speech, mind wandering with inner speech episodes was associated with greater bilateral inferior frontal activation and decreased activation in left temporal regions. This is consistent with the reported subjective evanescence and presumably reflects condensation processes.
In this way, it is an echo of the ego itself: a tiny control center sitting atop a vast subconscious and system of nerve impulses, explaining it to itself so that it can act on that smaller chunk of knowledge rather than being stranded awash in complexity.
Humanity struggles with a void within. Born with consciousness closer to that of the powerful, but trapped in little meat bodies, they rationalize their situation with negativity, portray themselves as victims, and never develop that inner voice into a source of power.