This is my post for day 5 of the Inkhaven writing retreat.

Epistemic status; spit-balling some stuff but confident in the overall concept.

Literally, physically, smaller. I don’t mean “lose weight”; I mean everyone should be like one meter tall. This would be highly advantageous to society and the economy.

Humans are pretty big for an animal. You might imagine that the reason we are the size that we are is because we need a body this big to support a brain this big. But I don’t think there’s any reason to believe that’s true! Shorter people are not less intelligent. We need to eat more to fuel our big brains, but our limbs are far stronger than needed to just carry our head around.

I think the reason we are this size is intra-species competition. If you’re taller, then you can beat up the other guy. So perhaps evolution slowly increased human height as we became more able to feed our bigger bodies. Or possibly we needed to be this tall for persistence hunting. In any case, neither of those are exactly “legitimate” reasons. I don’t think we would lose any of our deep human values if we all got our height cut in half. At this point we’ve mostly agreed not to fight, and we can handle the other predators with tools.

Okay, but why is smaller better? The two main reasons I can think of are 1) injury and 2) energy.

Injury

Small things are proportionally tougher. You can drop a matchbox car on the floor and it will just bounce, but if you drop a real car from four feet up you will need to call more than a mechanic. You can throw an ant off the balcony and it will just walk away, whereas if you faint from standing, you could easily bust your head open.

In these type of injuries, you get hurt because your body has to absorb the force of decelerating your own mass. Your mass is proportional to your volume, but forces are transmitted through surface area. A longer rope is not stronger, but a thicker rope is stronger. So when something twice as big falls, the mass it has to stop is eight times larger (two cubed) but its limb’s cross-sectional surface area is only four times larger (two squared). This disadvantage gets much worse as things get bigger (100 cubed is way, way bigger than 100 squared). This phenomenon is called the square-cubed law.

This is also why children are good at rock climbing, squirrels can climb trees, and bugs can climb walls.

So if people were smaller, there would be way less injury. Back pain would also be less common. Spooning with your partner would not have that awkward thing where your arm gets squeezed under them. You could also carry heavier things. Imagine going to IKEA and just hefting the whole bed frame over your head and sauntering home.

(You’d still get just as hurt if something else impacts you, like a bullet. Bigger people can take bigger punches, but falls are more dangerous to them.)

Energy

But the real winning reason why being smaller is better is that smaller things require less energy to operate, and everything in the economy scales with energy.

Our bodies would need less calories per day. Stores could be smaller. Farms could be smaller. We’d produce less carbon emissions. Cars would be smaller. We’d use less fuel. We’d need to produce less steel. Cities could be closer together. Our cargo would be smaller.

(“Wouldn’t we just have more children, until the population saturated our resources again?” I hear someone say. Yeah, probably. But more people means more positive experiences.)

Space exploration would benefit hugely from smaller people. The earth has so much gravity that we can just barely exit it with chemical rockets.

Because smaller things have less inertia, you can move them faster. All of society could go faster. That doesn’t mean you’d be more anxious; your neurons’ signalling would also have less far to travel, so you’d think faster, too.

The future

This is really all moot, because if the future goes well then we’ll all just upload our brains into computers, and “size” won’t be a thing anymore. But it’s fun to think about.