Subject says it all. Alcohol is considered harmless, but it isn't. That said, I don't support banning it. I just think it mostly isn't a good idea to use it for psychoactive effects.

--PM

You have very good points about the safety and waste disposal issues as advantages of fusion over fission.

Actually, I'm not claiming to KNOW that fusion will be uneconomical. I'm just AFRAID that it might forever be uneconomical. The capital costs seem monumental to me. By posing it as a question I was hoping someone who knew better would weigh in on the topic.

Honestly, I don't have a basis of knowledge on the topic to form any conclusion, and it's quite possible that until it is tried, no one *can* know with any certainty. If the answer is "no one knows", I support going on with fusion research until we figure that out.

--PeterM

Actually, I disagree that a fission plant and a fusion plant of the same capacity are "the same" in terms of complexity.

In a fission reactor:
You don't need superconducting magnets to contain the fuel
The fuel doesn't have to be kept in a near vacuum
You don't need lots of gyrotrons to heat up the fuel
The heat flux doesn't have to be kept away from the superconducing magnets
The neutron flux is stopped pretty much right in the reactor, heating the coolant, whereas in a fusion reactor the neutron flux is stopped mostly by the vacuum containment

I think a case could be made that these problems will translate into increased capital and operating costs that might well make fusion completely uneconomical compared to solar or whatever.

--PeterM

My big worry with fusion is that it'll be shown possible, but the cost per MW of capacity will be so high that you can't pay the interest on the cost of capital by charging competitive rates for electricity. Thus rendering fusion forever uneconomical compared to alternatives.

Nuclear fission seemingly has this problem right now, though much of the expense is due to implacable unreasonable opposition.

--PM

It'd help a lot if the life we're looking for feels like broadcasting really, really powerful modulated EM signals, directed mostly at likely habitats for other life (namely, us.)

--PM

Not necessarily any complete molecules. Water gets broken up and reassembled, by photosynthesis and other chemical processes (water breaks up spontaneously and rejoins, too.) But probably some of the atoms, yes.

--PM

There's a moral difference between CAUSING an abortion and ALLOWING one to happen naturally in the eyes of the religious.

To me, the line is more blurry. Is someone who could prevent something but allows it *completely* innocent, really? I mean, we as a society try to prevent deaths by cancer, why not deaths by natural abortion?

Also, some of the religious may argue that to cause an abortion that wouldn't have happened is to thwart God's Plan, but how do these yahoos know that the abortion wasn't God's plan?

And let's go back to the cancer deaths again. Are we not thwarting God's Plan by saving someone with cancer?

In the end, I think there is a fundamental point, the religious pick an arbitrary line between what they like and what they don't, and it doesn't always make rational sense.

I think the rational argument is that no one should be forced to risk their lives to provide life support to another person. My kidneys are MINE thank you very much, don't hook me up to another person as a dialysis machine against my will, even if it saves that person's life. It puts ME at risk and is a great imposition on me. And even if I agree to it at some point, I can change my mind about continuing to risk my life by providing dialysis.

Pregnancy is very much analogous.

--PM

Right you are!

If you're smart, it's mostly because you're lucky. You got the good genes. Then, you probably had a good upbringing and environment. Neither of which is anything else than luck.

Sure, to maximize your smarts, you have to work. But lots of people work hard.

So what makes high IQ people special, really? Luck.

What kind of asshole gets all hoity-toity because he was, mostly, lucky?

--PeterM

So, you realize that his person meant crony capitalists when he put free market capitalists in quotes, right?

--PM

You need to read that book.

Taking money for blood might have the opposite effect on the supply. In the book from the title, Swiss were asked if their community would be willing to host a nuclear waste storage facility for the good of the country. Many Swiss were on board with it--for the good of their country. A subset of Swiss from the same community were asked if they'd store the waste for $. Those Swiss said NO WAY. The good of their country was far more motivating for the Swiss than $.

And take me for example. $5 is in no way compensation for the enduring the needle stick and the time involved. I doubt $20 would motivate me. Maybe not even $100. However, I've donated 2 gallons or more. I do it because of this thought: one small needle stick for me, and a bit of time, and maybe someone gets to live.

And I'm the least-risk group of donors, selected partly by my lack of $ motivation. I don't need money for drugs because I don't take them. D'you really want to give drug addicts motive to donate blood to get money? Sometimes there isn't time for blood to be exhaustively screened before use.

Also, recent experience shows that the most powerful motivator for blood donation is solidarity. Blood donation went through the roof after 9/11 and other disasters. They literally couldn't stick people with needles and drain 'em fast enough.

I really think that if we want more blood supply, we need to beat the solidarity drum, and make it really convenient for people to donate.

Best,

--PeterM

This reminds me of isostasy http://en.wikipedia.org/wiki/Isostasy/ --as mountains erode, they rise again due to the buoyancy of the rock underneath them floating upon the magma below.

Pull out the mass of the water, and up go the mountains.

--PeterM

Unfortunately, slave labor and pirates aren't really rare.
Everyone in North Korea except the ruling class is pretty much a slave.

How free are the poor worldwide? I mean really, how free are they? In how many regimes worldwide do people have a really good shot at changing who their masters are?

What chains are YOU wearing that you're not even aware of?

--PM

Humans might be stuck, but our intelligent solid state mechanized descendants might find it less inconvenient to travel between stars. Just go slow, go into energy saving mode, except for continuous self-repair operations required to maintain functionality during the trip.

I don't think these hypothesized descendants would have much requirement for planets, though. Asteroids would be far better habitats, much more available energy and no big inconvenient gravity well.

--PeterM

On the contrary, if we flatline our population at a low enough level, we can maintain a high tech society indefinitely on this planet. The only materials we are truly consuming are uranium and other materials that we transmute to other elements. With enough energy input, we can recycle *everything* else. We can even take CO2 out of the air and turn it back into coal if we want.

It's simply a question of managing our resources for the long term.

And humans can do this, there was an isolated island in the pacific which maintained a good standard of living for hundreds of years via limiting population and managing resources until they were interfered with by outsiders. Their means of population control wasn't pretty--infanticide. However, we have better ways now to control population and in principle we could do the same planetwide.

Another example, the Japanese have re-forested their island, another example where humans can maintain and improve their environment, perhaps indefinitely. There's no need for the "herd" to move on if the "herd" maintains a good environment.

Just because humans presently are mostly NOT doing this does not mean we cannot.

Though I would prefer that humans self-modify so that they are more suitable for space habitats and move off the planet. The planet is only sustainable so long as there's no really big cataclysm of whatever sort.

So I agree with your point about colonization, however, I do NOT agree that 'using up the local resources' is the driving reason for diversifying habitat.

--PM

Let me play Devil's Advocate on grade inflation at Harvard and other Ivy Leagues. Harvard is so selective that only the best of the best have a hope of getting in. So why would you handicap the best of the best with respect to community colleges and give them bad GPAs? They are *all* A-class students, right? So why not give them all A's?

Second: what's so inherently wrong with the idea of learning without pressure? Who might be more qualified than the best of the best to do that? I.e., those who can get into the Ivies? This also reduces the incentive to cheat, and might create a collaborative environment rather than a cut throat one.

Were I a Harvard professor, I might do this: everyone gets A's and B's at worst, but rank people within the class and never share that internal ranking out of the class. That way, students get REAL feedback, know where they stand relative to each other, and have some incentive, but if they screw up relatively to the other awesome people in there, they don't get branded with a B or a C (or worse). I'd also focus in delivering frank and very critical assessments to these students to help the best become better. But the externally seen grades? Yeah, I'd inflate 'em.

As to "lack of quality", when you have such a grade of material incoming, I doubt that most anyone else will notice a 'lack of quality' in the product. Being lucky enough to be born smart is just such an advantage it's really hard to screw that up.

--PeterM