In my development as a critical thinker (still developing yo') I was often abrasive and strident in presenting my views. Often, I would latch on to my beliefs and arguments and miss out on those of others. The common case of talking past one another.
In my crackpot bashing days on Usenet, I developed a hair trigger when dealing with what I perceived as ignorant or downright stupid statements.
I will occasionally post some worthwhile examples of my younger days. Some of the assertions I still belive, some I do not or have modified. But the main lessons to take away from these "Blasts from the past" are:
1. Learning to think critically is a life long process.
2. After you have vented your emotions, be willing to go back and look at your assumptions and arguments.
3. Applying critical thinking skills have similar results as applying any skill... namely that since we are imperfect sacks of mostly water, we cannot perform any skill perfectly.
And finally, as a result of the above:
Critical thinking does not 'have' to give us the answers.
Equally so, others pessimistically shortchange the ability of man to
(Here I am still pissed about the negative ninnies Luddites I had previously dealt with.)
We all know that there is no free lunch, the second law sets this limit.
However, many do not realize its application to closed and open systems.
Our population problem comes down to a few factors (which interact in an
astoundingly complex manner).
A short list:
2. Raw materials
3. Habitable volume
> likely to take more than the handwaving about our uncertainties about
> the laws of physics that Simon appears to offer in his chapter 4.
> I think - in the absence of other evidence - we should go by the laws
> physics as they are currently understood.
technology that exists or can exist in say 100 years.
Be careful when you state "laws of physics", when actually it has more
to do with our state of technology.
Lets consider 1. Energy:
Lets do a Fermi type problem.
Radiant energy from the sun at earths orbit is around 1400 W/m^2
Surface area of the moon: 4x10^13 m^2
Area exposed to the sun at any one moment: 2x10^13 m^2
Total solar energy available on surface of the moon: 2.5x10^16 W
Say we utilize 1/10% of the surface for solar collectors: 2x10^10 m^2
This would correspond to a band of solar panels surrouning the equator
of the moon with a width a little over 3.5 km
Available solar energy: 2.5x10^13 W
Lets be pessimistic an say we have really crummy solar collectors with
low efficiency broad band spectrum of 1%
Collected energy: 2.5x10^11 W
Conversion to microwave energy, pessimistically 10%
Energy at microwave: 2.5x10^10 W
Transmit collimated microwave energy toward earth, with a pessimistic
90% loss due to atmosphere, inverse square, etc.
Energy at collection stations around earth: 2.5x^9 W
Predicted power usage by 2020: 25 TWh
Therefore we would need a power output of 2.9x10^9 W to meet our energy
Note that the total efficiency of the plan outlined above is 0.0001%
Which is a exceedingly pessimistic. For each order of magnitude
increase in transfer efficiency, we can decrease by one order of
magnitude the total collector area and still get our 2.5x10^9 Watts.
How about construction materials on the moon?
The surface is mostly silicates... perfect for constructing solar cells.
(The point here is that, regardless of the tech difficulties of such a construction project, launching, man hours etc. the physics allows this, and who can say what technology will be like in 100 years, or 500 years! But people are too quick to assume that we are peaked with what we can accomplish.)
> finite times there.
course we don't need to.
People 90 years ago had nearly the same understanding of physics as we
do now, but do you think we had the technology 90 years ago to supply
the same amount of energy as we can now? Food? Distribution?
The key to population support is energy production and usage. And will
be even more so in the future.
(Now... is it really the key to population support?)
> currently seems more likely to me.
heat death of the universe.
Hey... I STILL firmly believe this! ;) But try convincing my wife of that... [8(
There is no "infinite energy", and we don't need it.