Experiences living in my own societal bubble.
Note that at no point am I belittling or demeaning others nor boasting about myself. This will be reiterated throughout.
Herrnstein and Murray's thesis of The Bell Curve was that society is becoming increasingly stratified by intelligence, with the Cognitive Elite forming the most successful group and the non-Cognitive Elite forming the remaining.
The third paragraph of Part I—titled "The Emergence of a Cognitive Elite"—describes it succinctly:
Cognitive stratification takes different forms at the top and the bottom of the scale of intelligence. ... In Part I, we look at the top. Its story line is that modern societies identify the brightest youths with ever increasing efficiency and then guide them into fairly narrow educational occupational channels. These channels are increasingly lucrative and influential, leading to the development of a distinct stratum in the social hierarchy, which we hereby dub the Cognitive Elite. The isolation of the brightest from the rest of society is already extreme; the forces driving it are growing stronger rather than weaker. Governments can influence these forces but cannot neutralize them.
While I do not consider myself part of the Cognitive Elite, I do consider myself smarter than average and fortunate in many other ways, both genetic and non-genetic:
Most of my core group of friends are also in similar circumstances. Most grew up in fairly nice areas with married parents who had stable jobs, attended a higher education institution for some amount of time, and currently work at some job. I have few friends/acquaintances who deviate very far from my situation. Sure, there are extreme outliers (all acquaintances) from middle or high school who end up on the bottom extreme (which is much more likely than the top extreme), but most of my friends are right up around me.
I first noticed the stratification during my second year of high school, when students began having more options for pre-AP (Advanced Placement) and AP courses. The same 100 or so kids (out of a 730-large graduating class two years later) all took the same (pre-)AP courses, rarely opting for a "regular" (no AP in the course title) course. Besides electives that didn't offer an AP option, I never took a regular course past my second year. (Like others, the reasoning was two-fold: taking AP classes provided a massive GPA multiplier and doing well on an AP exam provided college credit.) This pattern continued throughout the next two years, culminating at the graduation ceremony. The Latin honors went first: I knew every summa cum laude, almost every magna cum laude, a decent amount of the cum laude, and relatively few non-honors. Other summa friends had the same experience. I'm sure the converse was true, too: non-honors students probably knew very few of the honors. (Once again, not boasting.)
This experience extended to my time at university. While there was quadruple filter applied by the requirements to get into the university, then the College of Engineering, then the electrical engineering department, and finally by the rigor of the courses, strata were still formed within the already-cognitively-advanced population. Some students stood out in the more difficult courses, becoming a beacon for confused students to ask questions and get help, while others struggled with the curriculum. When the Latin honors graduates were announced, I knew a majority of all three tiers. (This can also be attributed to the smart ones always asking questions during tests, as well as me seeking them out for help on assignments, rather than just automatically being associated with them like my high school peers.) (Once again, not boasting.)
But the filters and stratification do not stop with schooling, continuing on to careers. Companies filter applications by intelligence through GPA requirements, IQ tests, and sometimes even alma mater. Higher-up promotions are determined not by time spent with the company, but by contributions made, which are often dependent on intelligence. As Herrnstein and Murray discuss:
To be a first-rate lawyer, you had better come from the upper end of the cognitive ability distribution. The same may be said of a handful of other occupations, such as accountants, engineers and architects, college teachers, dentists and physicians, mathematicians, and scientists.
Of course, there is still overlap between strata, but it's generally brief and infrequent:
This does not mean that a member of the cognitive elite never crosses paths with a person with a low IQ, but the encounters that matter tend to be limited. The more intimate or more enduring the human relationship is, the more likely it is to be among people similar in intellectual level.
To check how thick my bubble is, I took a 25-question quiz in one of Murray's recent books, Coming Apart. The following are my answers, in order: no, (yes, no), no, no, no, (yes, yes, no), no, no, yes, no, none, (no, no), yes (I'll count my family), no, yes, (0, 0, 0, 0, 0, 0, 0, 0, 0), yes, no, no, no, ridden, (Jurassic World, Mission Impossible: Rogue Nation), none, none, Richard Branson.
I got 22 points. Here are the "scores Charles Murray would expect you to get based on the following descriptions":
11–80: A first-generation upper-middle-class person with middle-class parents. Typical: 33.
0–43: A second-generation (or more) upper-middle-class person who has made a point of getting out a lot. Typical: 9.
One of my favorite YouTube channels to watch is All Gas No Brakes, now Channel 5 with Andrew Callaghan. Callaghan reports on a variety of eccentric topics, including bigfoot hunting, border security expos, and pick up artist bootcamps. While partially meant to be comedic, there is an element of serious journalism embedded within the videos: hearing the voices and stories of these people and events that most of society has no clue exists.
In watching these, it dawned on me just how "bubbled" I was. I don't know anyone who believes that Kobe Bryant was assassinated or that aliens that are being programmed with occult magic to conduct a planetary takeover or spends $100/day on alcohol. Because people in my bubble hold fairly reasonable beliefs (sorry, those beliefs are unreasonable) and act with fairly normal behavior (sorry, blowing $100/day on alcohol is abnormal), my exposure to those with so-called "crazy" beliefs is minimized, the number of people who I think have crazy beliefs is greatly reduced, and the belief that most people are like those in my bubble is reinforced. It's only when I step outside of my bubble that I'm brought back to the reality that I only experience a small part of society.
But this is relative and subject to the beholder. Similar experiences can (likely) be found on the other side of the spectrum: Kobe was assassinated, occult aliens are inevitable, and dropping fat stacks daily on bottles of Henny is normal. The people that believe in and do those things live in their own bubble, one that is just as normal as mine and equally far away.
All this to say like surrounds like. Our bubbles consist of others that are similar to us in many regards, whether it be through interests, intelligence level, occupation, or something else.
This has obvious implications. We are much more likely to assume that others outside of the bubble are like those in it. This assumption influences our behaviors and expectations of others. Our idea of "normal" is reinforced by the bubble's inhabitants, when it may actually be abnormal.