Making such proclamations as “smart people spend more time alone” will have every extrovert who is reading this scoff (as introverts rejoice).
“That’s NOT true!!” They will cry, en masse. Extroverts, I hear you. As an ambivert, I empathize with both sides.
So, the basis for this assertion comes from the idea called the savanna theory of happiness, which has demonstrated that socialization and intelligence are ancient structures, and that our ancestors who spent more time alone had more time to adapt to change in their societies. Perhaps they could better assess their tools and infrastructure, perhaps they could better see where politics were going better than their friends who joined in social gathering.
That, anyway, is the idea. As this source describes, “”Spending time with friends is a very natural activity that was likely necessary for survival over millions of years,” Dr. Norman Li, associate professor of psychology at Singapore Management University and co-author of the study, said in an email.”High general intelligence might allow people to better handle new things that humans only recently are encountering, such as managing one’s life using computers, smartphones, etc., and not needing (for survival purposes) to associate with friends on a daily basis,” he posited. “So, it’s more like high intelligence might allow people to more comfortably live outside of natural conditions.”
The implication is that humans had to be social to survive: bringing a wildebeest down on the savanna requires deliberate and thoughtful planning between a number of people. And for many circumstances required by tightly-knit, nomadic ancestral community, it made perfect sense to rely on others for certain things, like, to eat.
But the suggestion is that the study indicates that humans are happier with more social interaction generally, except for one thing: people who are happiest with fewer social interactions are generally more intelligent.
As I can hear the cry of the extroverts mounting, I might remind them of one thing: I used the word “generally” in the last paragraph. There are plenty of indications that extroverts can be smart as well. It’s just a rather interesting, seemingly contrasting, correlation found within the controls of the study: introverts do tend to be more intelligent people. Just as any other study involving intelligence and personality, there are plenty of exceptions to the evidence.