# How many people is too many?

## Plus, those funny tricks your eyes play on you

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Question: How many people would you estimate are in your personal "clan"—family and friends with whom you interact on a regular basis? Why is 100-200 your likely limit?

Answer: Because that's about the population of a prehistoric village, which is near the "design limit" for human relationships — the maximum number of individuals with whom a human being can interact at more than a superficial level, say Robert Ornstein et al. in "New World, New Mind."

Beyond that, overload sets in. For it's not just the 100-200 you have to keep in mind, but their relationships as well. Think just of your immediate family of say 6: A B C D E F. In addition to the 5 others (you're A), you need to keep in mind how B relates to C (B-C), also B-D, B-E, B-F, C-D, C-E, C-F, D-E, D-F, E-F. Among 6 family members, that's (6 x 5)/2 = 15 2-person relationships to know. You can see where this is headed.

Make that an office of 20 and there are 190 possible relationships to worry about. In a village of 100, 4,950. For a modern big-city school of 3,000, 4,498,500! This is way beyond anything even remotely conceivable, "yet much of humanity today lives in cities of 10 times that population and more."

Question: How do you rudely cut in line and get away with it?

Answer: Get away with it maybe, just hope that Attila's not queued there. From the book "Cheap Psychological Tricks: What to Do When Hard Work, Honesty and Perseverance Fail," by Perry W. Buffington, Ph.D., you brazen up to cut in near the front, figuring folks there have almost made it and won't see you as a threat. Plus, the line-headers will likely be in a good, charitable mood by that time.

You'd think cutting in farther back would be easier, but this is the "worry zone," where queuers fear investing time only to be cut off near the ticket window, or whatever.

In one study, three-quarters of midline or later cutters drew complaints, compared to a quarter near the front.

Another tack, notes "Greta Garbage's Outrageous Bathroom Book," is to request to cut in BEHIND someone near the front — totally ridiculous since it's no skin off that person's nose, so on what grounds may this permission be granted you? Which is exactly why this might work, leaving the rearward folks flabbergasted.

Question: What does it take for the world to disappear before your eyes? Think optics, eyeball jiggle and Jurassic Park.

Answer: Start with the flip-flop optics of your eyes' lenses actually painting the world upside down on your retinas. To compensate for this inversion, your body's map on your brain is also upside down — keeps the map in synch with visual space — says State University of New York neurosurgeon James Holsapple. "In this sense, your brain is hanging by its toes in your cranium!"

Now do something bizarre and put on a pair of image-inverting glasses, so immediately the world seems to have done a 180-degree somersault. Not much fun. You stumble over everything, can't walk, shoot pool, read your e-mail.

But just wait. Within about a week — still with it? — your brain learns to adjust. Things still appear upside down, says Hope College psychologist David Myers, but you can walk comfortably, reach out and grasp objects. In studies, glasses wearers have even ridden a motorcycle and skied the Alps. The brain re-maps, so to speak.

Now take this one loony step beyond, poses Holsapple, and fit on gear that perfectly stabilizes images on your retinas, by compensating for your eyeballs' natural restless jumpiness. Now within just 10-20 seconds, the image simply vanishes, and you're left staring at a gray field!

So it is necessary for an image to be sliding around or changing all the time for us to SEE. "Like those dinos in Jurassic Park — that failed to see the troop of lost campers because everyone is holding very still — we too require some amount of motion in the visual world for it to be seen."

Send STRANGE questions to brothers Bill and Rich at (strangetrue@compuserve.com).