Energy and Human Ambitions on a Finite Planet, 2021a

D.5 <strong>Human</strong>ity’s Long View 405
In order for human civilization to be in its infancy, it would have to
continue for at least 10,000 years more, if not far longer. What would it
mean for us to still be operating “successfully” 10,000 years from now?
Our physics <strong>and</strong> math approach actually allows us to place constraints!
This discussion is limited to living on Earth. Chapter 4 laid out reasons
why imagining a space-faring future may be misguided. But even
ignoring these arguments, Chapter 1 illustrated that human growth
ambitions would be brought to an end long before 10,000 years pass.
In this light, it is most straightforward to concentrate on what it would
take to succeed on Earth itself. 46
If we manage to carry our civilization into the far future, 47 we can
comfortably call this success. If we don’t, well, that would be failure.
Can we sketch out what success looks like? One easy way to get there is
to start enumerating the things that can’t be carried into the far future.
1. Fossil fuels will not power civilization: a large fraction of the initial
inheritance has been spent in a short 200 years, 48 so that 10,000
years in the future it is safe to say they will be long gone.
2. No steady annual decline of natural resources like forests, fisheries,
fresh water, or species populations can be brooked. Allowing any
component to decline would mean eventually losing that resource,
which may be critical to our survival.
3. <strong>Human</strong> population will not be allowed to grow. Even small growth
rates will step up pressure on natural resources, <strong>and</strong> Earth can
only support so much, long-term. Independent of what the “right”
number is, 49 once settled, we will not be able to dial it up without
imperiling the hard-won success.
4. Even under steady human population, any increase in resource
use per person will also not be compatible. In general, growth
leads to a dead end: to failure.
5. Mining materials from the Earth will not continue at anything near
the current pace. In the last few hundred years, the best deposits
of copper, gold, aluminum, etc. have been found <strong>and</strong> exploited.
Even if only 10% of the attainable resource has been consumed
thus far, 50 continuing for tens of thous<strong>and</strong>s of years (<strong>and</strong> beyond)
cannot be expected.
6. Ultimately, any activity that draws down a finite natural resource
will be impossible to sustain if the extraction rate is modest or high
in relation to the initial resource abundance. Anything that can’t
last for well over 10,000 years is not a viable long-term solution
<strong>and</strong> should not be exploited if success is the goal. Likewise, any
pollutant that can build up to dangerous levels on even these very
long timescales cannot be tolerated, if failure is to be avoided.
7. We can use the rule of 70 to say that anything having a doubling
time (or halving-time in the case of depletion) shorter than 10,000
years is a no-go for success on these timescales, meaning that any
activity impacting resources would have to be held to a growth rate
46: Even if extending to other planets, the
same logic will apply.
47: A useful definition might be uninterrupted
preservation of the knowledge <strong>and</strong>
history gained thus far, without some apocalyptic
collapse forcing a start-from-scratch
revival—to the extent that’s even plausible.
48: . . . most of this in the last 50 years
49: . . . unlikely as high as 10 billion, <strong>and</strong>
it could even be well less than a billion,
depending on living st<strong>and</strong>ards
50: . . . author’s conjecture; it could well be
higher
© 2021 T. W. Murphy, Jr.; Creative Commons Attribution-NonCommercial 4.0 International Lic.;
Freely available at: https://escholarship.org/uc/energy_ambitions.