Understanding the limits of reality

We have come incredibly far as humans from mud huts to the International Space Station, and many times throughout our history people have proclaimed that the end was near, only to be disproved by technology’s eternal march forward.
Today we too face great problems like climate change and so-called unsustainable growth, but how do we recognize whether our fears are just as ungrounded as the ones voiced by people of the past or if we really should have great concerns?
I argue it all comes down to reasoning about what is possible, concidering the barriers the laws of physics has set up for us and thereby understanding the limits of our reality. When we do this, we see just how incredibly far it is still possible to go and that our future has the potential to be insanely great.


For the past 10,000 years, our world has seen profound changes. We humans have advanced from a time where our most complex inventions were cave paintings and mud huts to the present, where our capabilities count moon landings, airplanes, a high-tech global civilization, the internet and much much more.

Especially the last 200 years have seen these magnificent changes come about so fast, you don’t have to go many years back to find a time where our present world would seem literally impossible to people alive back then.
Imagine time traveling back to the 1850’s and tell an average person about the fact that we can access the entirety of the human knowledge and media in seconds from a device that fits in our pockets. And on this device we can look at high-definition pictures of distant galaxies or watch giant metal birds containing hundreds of people seemingly defy gravity while they take us from one side of the earth to the other in hours.
All of this would probably be considered completely impossible and not within the realms of the possible. Clearly this is wrong; the miracles of our present time is very much part of reality.

Futuristic thinking gone wrong

This inability of people to imagine the future correctly has very often created a lot of doom and gloom visions of the future.
A prime example of this comes from Thomas Malthus, an english revenant from the 18th century who influenced the fields of political economy and demography.
He observed that our population was growing exponentially and this growth had no end in sight. This, he argued, would cause massive global famines because our food production couldn’t possibly keep up with the rising number of people. Therefore the only reasonable outcome would be a global hunger crisis lasting until so many people had died that our food production once again was sufficient.

This, luckily, turned out not to happen. Malthus was completely correct in his observation that the population grew exponentially, but he failed to take the powers of technological progress into consideration. In reality, our food production rose much quicker than the number of people did, and today we are 8 times as many people as in Malthus’ time but with 1.6 billion of them overweight, more than twice the number of malnourished people.

This is by no means the only example of doomsday prophecies which turned out to be duds because of the relentless progress of science and technology. It seems to be a recurrent theme of humanity to underestimate the possibilities of the future.
Today we also have a lot of doom and gloom mentality around us. Climate change, overpopulation, unsustainable growth, the depletion of the earth’s resources etc, there seems to be quite a lot of reasons to fear for the future of our species.
But how do we figure out whether our present day apocalyptic visions are just a continuation of yesteryears failed doomsday prophecies or if there actually is a proper reason for concern?
How should we think about the future so as not to fool ourselves about what is possible, as so many people have done throughout history?

First of all, I am going to give an example of how not to think. Many people make this mistake, so it is very important to really understand the following: When thinking about the future, do not just imagine an upscaled version of the present!
Let me illustrate this fallacy through an example.

Imagine we could ask a native american from the 1600’s to imagine what future communication technologies might be like.
This native american could take starting point in what he knows, smoke signals perhaps. Then he could extrapolate this technique into a much better version of itself: Perhaps future smoke signals could rise as high as clouds, be just as big as clouds but incredibly detailed and last for days! How incredible wouldn’t that be!
But as this person would hypothesize about the amazing smoke clouds of the future, information would be flowing above him, under him, around him and through him at 300,000 km/second. Invisibly and silently complex information containing articles, books, pictures, videos, 3d-simulations and whatever you can imagine would race around the world delivering itself to billions of people instantly and effortlessly at the push of a button.
This is the difference between just imagining an upscaled version of the present and the actual future. Technologies of the future are very often profoundly different from the present.

If it is not physically impossible, it is possible

Then how should we think about the future if not an upscaled version of the present? The foundation of my proposed framework for futuristic thinking goes like this: “If it is not physically impossible, it is possible”. This seems self-evident and tautological to the point of silliness though, so why is it so important?
First of all, many people do not actually get this idea. Whenever someone is saying something like “We will never be able to do something something something” that person is most likely breaking this fundamental, “obvious” rule. Unless he talks about breaking the speed of light, creating a perpetual motion machine or time travel, there probably is no reason to believe it is physically impossible, hence it is possible, hence it is unwise to just dismiss the idea.
A phrase I have heard a few times, to say the least, goes something along the lines of “We will never have electric cars better and cheaper than gasoline cars”, and really, never? Unless the laws of physics truly prohibit the development of good, affordable electric cars, this statement is grandiose and short sighted to an almost silly degree.
If you don’t believe something cannot be developed simply because it is not feasible with current day technology, you have made the horrible fallacy of believing we can never invent anything new ever again, and from here on out it is all down hill. That is obviously quite ridiculous.

Instead, reason from first principles about what is allowed and what is not given the known laws of physics. When you do this, you get a much clearer picture of what is truly possible and what is not.
Let’s use this technique to tackle some of our greatest challenges we face right now: climate change, overpopulation and the depletion of earths resources.

First up, climate change. What is the problem? The problem, stated simply, is that we have an ever growing need for energy but our current energy supply pollutes the atmosphere and creates extremely damaging climate change (among other things).
One solution could be to severely cut our energy use. But this seems quite unlikely since billions of people are now crawling out of life-destroying poverty and want to live the blessed life of us westeners, and who can blame them?
A different solution is ‘simply’ to get our energy from different, non-polluting sources. But from where, and is there enough of it? Luckily, the sun bathes us in more than 10000 times as much energy as we humans currently consume (1.74·10¹⁷W vs 1.26·10¹³W) and it is all carbon neutral. So it is just a matter of collecting it. But if we look at the speed at which the solar industry has grown for the past 25 years, in 17–25 years time about 50% of the worlds energy needs could be supplied by solar, and a few years after that it could approach 100%. Problem solved!

Overpopulation and scarcity of resources go hand in hand, since the need of resources is primarily the concern of overpopulation.
So are we running out? Well, we just argued that energy doesn’t have to be a problem unless we suddenly spike our demands by a million percent (which seems just a tad unlikely).
What about raw materials? There is about 2·10¹⁸ tons of aluminum in the earths crust, which turns out to be a bit over 45 billion times our annual production. No worries.
Iron? 1.25·10¹⁸ tonnes or over 1 billion times our annual production.
Sodium? 7·10¹⁷ tonnes or over 2.5 billion times our annual production. This pattern is true for just about any element we really need. Granted, there isn’t much palladium in the earths crust, but who cares?
So raw materials are no problem. What about water? There is plenty of water on the surface of this planet, about 1.386 billion cubic kilometers actually, but only 0.5% are available in readily drinkable form. The solution? Desalination. The problem with this solution? Mostly high energy and maintenance costs of the desalination plants. The solution? As earlier argued, energy need not be a problem and with automation the maintenance costs can be reduced to a fraction of today’s.

Alright, the next one is more tricky: food. Right now 38% of all of earths land masses are used in agriculture, so it would be quite a problem if suddenly our food production had to increase two or three fold. But there is a way out. In the past the agricultural output per area was many times lower than it is today, so if it is possible to continue that upwards trend forward we could produce many more times the food we do today on much less land.
But is this possible? I see a couple of ways out. One of our very promising techniques is gene editing, and with technologies like CRISPR gaining a lot of attention and money, we could have very sophisticated ways of editing the genome of our future plants and animals. We have already transformed the natural plants of the past into grotesque monsters of their former selves. Wheat from 10,000 years ago probably didn’t have much more than 5 or 10 corns per stilk, today you can get 80. Natural apples are small, disgustingly sour and filled with seeds; today they are giant, wellformed, sweet and delicious and our trees have many more of them.
This we achieved with extremely crude gene editing tools, mainly breeding plants with features we liked. How far can we go with actual control over the plant genome?

But this is only the beginning. The concept of indoor farming is starting to gain popularity. With indoor farming you stack plants in many levels in giant, indoor climate controlled environments where LED’s produce just the right frequency of light to optimize growth while minimizing energy use.
In these environments there are no pests, no disease, only perfect climate and perfect light. Imagine if we scaled up these rather small present day experiments to billions or trillions of plants. Then we could monitor every single one of them with advanced censors that could take high-def images of every single angle, monitor pH-levels, water levels, chemical composition of the leaves, genome sequencing and more. This would generate truly massive amounts of high quality data. Then we could throw our most advanced and capable data mining-, machine learning- and statistical techniques at this magnificent gargantuan of an ever-growing food-data mountain to continuously garner insight otherwise completely hidden from us.
How far could we go? Honestly, I have no idea, but I find it reasonable to believe we have only scratched the surface of optimizing agriculture even though our current knowledge and skill has been 10,000 years in the making.
The main problem with indoor farming right now is very high energy costs, but if you buy my argument that we have an insane untapped potential for energy collection, this should be a feasible challenge to overcome.

What about space? The stereotypical vision of an overpopulated future is one with claustrophobic conditions anywhere you go with people on top of people on top of people.
So let’s analyze the possibilities! Today about 55% of the human population lives in cities covering just 3% of the earths landmasses. The problem is that 40% of of our planet is used in agriculture. But if we just made our food production 10% more effective that could potentially free up enough space to rebuild all of the world’s cities once again. And only a 10% increase seems like an absolutely pathetic goal to achieve.
So we have more than enough space, given that we can optimize our agriculture.

So as you can see, we need not worry at all! Well, you might think that I have just slightly glossed over some quite important details and have reduced some incredibly complex problems to a set of vast oversimplifications, and you would be absolutely right.

My point here is not to devise an airtight plan for how to solve the worlds greatest challenges, but to illustrate a specific way of thinking. My goal is to show how one might go about reasoning about the possibilities we have to make progress as a species.
What I hope to have shown is that just as easily as you can argue for why we are all doomed and the future must be horrific, you can argue for the exact opposite scenario.
However, all this happy thinking need not come true at all. The only way this can become a reality is, if we as a species continue to relentlessly push ourselves further and keep alive our ever expanding march of scientific and technological progress.
We need this drive to envision what is possible, otherwise we have no hope of ever accomplishing it.

A glimpse of just how far we can go

In the last part of this article I will go all out on the futuristical thinking. The ideas I present here might seem a bit crazy, and maybe they are. But what is crucial to remember is that none of it is prohibited by the laws of physics, and therefore it is reasonable to assume that it might become reality some time.
I hope to give you just a tiny glimpse of the incredible and awe-inspiring depths with which the limits of reality provide us.

The first thing I want get into is the amazing promises of nanotechnology. This field was first proposed by Richard Feyman in 1959 in his classic lecture “There is plenty of room at the bottom”, and later made much more rigorous and scientific by Eric Drexler.
The insight of nanotechnology is that any kind of manufacturing fundamentally is the reordering of atoms. Our current manufacturing methods move trillions and trillions of atoms a time though, so what if we could move them one by one? This isn’t prohibited by any physics, and our body actually has trillions of tiny machines doing manufacturing just like that. We just call them enzymes.
So imagine some kind of machine that fits on a table. You feed it raw materials in one end, and out the other comes atomically precise goods where every atom is placed correctly. Then the only costs of products would be the energy costs of our machine and price of raw materials. Just about anything we use in this world is comprised of carbon, iron, aluminum, silicium, titanium, oxygen, hydrogen, nitrogen and phosphor, but all of these materials costs pennies per kg. So if you wanted some new, perfectly fitted luxury clothes of a quality unknown to man today, you could create if for pennies per kg. We could all have the materialistic opportunities of millionaires or billionaires today, actually much much better. No product today made by our incredibly crude methods can compare to atomically precise manufacturing. An you will get it all for pennies per kg.
The same goes for food. Food is made out of carbon, oxygen, hydrogen, nitrogen and phosphor. Pennies per kg of food in unlimited supply to every person on earth.

But nanotechnology can be used to much more than just producing goods. We could potentially make billions of small, perfect nanorobots that could venture into our bloodstreams and fix up any kind of cellular damage we might have accrued. Cancer? Send in those nanorobots to puncture holes in the cancerous cells until they are all dead and gone. A broken spine? Send in perfectly tailored nanobots to build up new cells and fix up the damaged ones. Any kind of defect anywhere in your body? Nanobots to the rescue.
What is the effect of this? One of them is the absolute and indefinte defeat and reversal of aging. No more growing old, wrinkled and weak. You can live for hundreds or thousands of years in perfect, beatiful health if you choose to.
But why stop there? Our body is nowhere near what could be described as ‘perfect’. How much better could we not be if we had the ability to improve on the hack-job that evolution has created and actually intelligently design the human body?
Some people are already thinking along these lines, and someone has designed a hypothetical bloodcell-machine that stores oxygen hundreds of times more effectively than our hemoglobin proteins do. Do you want to sprint 10 km without needing to take a breath? Well ‘now’ you can.
How about the ability to jump meters into the air and bend steel with your bare hands? It is absolutely possible to create machines with these capabilities therefore we could potentially get them too.
I could go on and on with engineering of the human body, but I hope you get the picture.

But won’t it be a problem if nobody died and the planet filled up on humans? First of all, production of food, goods and energy shouldn’t be a problem considering nanotechnology, solar power and maybe fusion power.
The problem might be room for us all. One solution could be the construction of giant self-sufficient habitats. With stronger building materials, these could be enormous, 100 story tall buildings housing thousands of people and being completely self-sufficient. They could have a basement with nanofactured food production and all the goods the people would need.
A 100 stories tall building with a base of 4–5 hectares, roughly the size of a circle with a 125 m diameter, could house 5000 people so that every single person gets an average of 1000 square meters to live on.
This is more than enough to live quite comfortably, and at 1000 people per hectare, fitting trillions of people on this planet should be a piece of cake.
And these trillions of people is to say nothing of colonizing the other planets in our solar systems and creating billions of giant habitats in space orbiting around the sun made out of asteroids and moons.

(A little caveat here: I haven’t provided any details or proper scientific reasoning for these visions, but just stated them. This is mainly because of a practical issue. This article is already over 3,000 words long, and my goal is more to pique your curiosity than to make rigorous and detailed arguments. I have provided af few links with much more information for the so inclined.)

You might think that this just sounds like fantastical pie-in-the-sky thinking, and to some degree, it is.
But the ever important thing to remember is that none of this is by any means prohibited by any known laws of physics. I have on purpose not mentioned faster than light travel or perpetual motion machines, because these are impossible (as far as we know, anyway).
And although these ideas can seem a bit crazy, I haven’t nearly scratched the surface of how far you can go. These were just the very first sentences of an (almost) never-ending story about the limits of our reality.



More info about nanotechnology, human engineering and self-sutaining habitats

Nanotechnology and human engineering
https://www.pa.msu.edu/~yang/RFeynman_plentySpace.pdf
http://www.nanotech-now.com/columns/?article=832
https://www.youtube.com/watch?v=Q9RiB_o7Szs
https://www.youtube.com/watch?v=lvUFNp-TWbg
https://www.youtube.com/watch?v=zQHA-UaUAe0
https://www.foresight.org/Conference/MNT8/Papers/Rubinstein/index.html
http://dujs.dartmouth.edu/2010/03/artificial-blood-an-elusive-medical-grail/
https://www.youtube.com/watch?v=T0lvxTm2iLg

Self-sustaining habitats and other interesting stuff.
These videos are all from the same channel by a guy called Isaac Arthur. They are all incredibly fascinating and take the futuristic thinking grounded in reality to the extreme. Recommended for anyone interested in this topic who likes rather in-depth explorations of what might be possible one day.
https://www.youtube.com/watch?v=TqKQ94DtS54
https://www.youtube.com/watch?v=8Pmgr6FtYcY
https://www.youtube.com/watch?v=86JAU3w9mB8