Sounds like a good-enough definition of truth for me.

I wonder how well their predictive ability would have worked when i bought my computer. I was all ready to buy a Mac and then was convinced otherwise. Maybe my brain knew it all along and I never really “changed my mind”.

This is a pretty simple example (choosing which button to press). I want to see them do it with a much more complex situation. The responsible thing to do NOW is to find out when you CANNOT predict what decision someone will make and then work backwards to figure out where it breaks. This way they can try to understand the differences between situations where you can predict someone’s decisions, and those when you cannot, unless you always can…

I also want to spend a moment to explain my problem with “people are sheep” statements like the previously mentioned line from your post (”The average person doesn’t have a very strong penchant for critical thought”). While I realize there is evidence to support the claim that humans are influenced by authority, there is also evidence to suggest that expertise and context have a great deal more to do with the application of “critical thinking skills” than simple herd mentality. The book “How People Learn”, a publication of the National Research Council, is available for free online and I would point to the sections on How Experts Differ from Novices (section 2) and Learning and Transfer (section 3).

I will add only that people are able to, and frequently do, apply their skills differentially according to their beliefs and expertise. If someone wants to be connected to their social group, they may “believe” in intelligent design without giving it much thought, even if they use critical thinking skills daily in their profession. I agree that your revision to “broadly skeptical” is more accurate.

“Expelled”, like many films with an agenda, are mostly preaching to the converted. They don’t need to make a very strong case. They just need to bolster the faith of their constituents, give them a few new arguments, and some jokes to tell about the folks on the other side. I, for one, am encouraged by the fact that ID proponents are concerned enough to start making films that further publicize the discussion.

What I really intended to indicate was the average person doesn’t have a very strong penchant to be broadly skeptical. I still won’t offer support for that, but I think it’s more accurate.

Specifically, at today’s price of ~$40/kG of uranium, the ore costs amount to only ~0.1 cents/kW-hr (i.e., only ~2-3% of nuclear’s total power cost). The ore cost could increase by a factor of 10 (to ~$400/kg) and nuclear’s power cost would only increase by ~1 cent.

However the problem with your question is that it depends on which fuel cycle that is assumed and what model you use to estimate unknown reserves.

Currently the once-through cycle only uses a fraction of the fissile material in it. Thus spent nuclear fuel still has from 95 percent to 99 percent of unused uranium in it, and this can be recycled. As a consequence at current consumption we have about 600 years of burnable fuel above ground already.

Now your next question will be is reprocessing viable from the energy ROI perspective, and the answer is yes. What it is not is economically viable and that is because current prices for new uranium are too low.

And this is not all. The most popular types of reactors require the fuel to be enriched to increase the concentration of the key isotope U235. Right now as it stands a good deal of this is left in the tailings but again at the cost of fresh uranium it is not cost effective to extract it.

The low price of uranium has also means that exploration has not been given the priority that it would be if prices were higher.

In fact Uranium resources from conventional sources compare very favourably with most other resources. Virtually no exploration for conventional uranium sources has been undertaken during the last 30 years. Most of the world’s land surface has yet to be explored for uranium. It is economically possible to extract uranium and thorium from phosphate ore and mine tailings, but this is not done because of the abundance of conventional supplies. This source alone amounts to millions of tons of both uranium and thorium.

As well there are a number of placer deposits of both ores that have been identified but at the moment are not economically viable, again because of low prices. Also the Japanese have demonstrated that it is technically economically possible to extract Uranium from sea water using low energy techniques, but again it’s sill cheaper to buy on the open market.

Breeder reactors have been maligned as an unproven technology. The fact is they have been in regular use for decades breeding plutonium for nuclear weapons. It is a mature technology that simply isn’t worth the cost at this point. Construction of the Clinch River Commercial Breeder Reactor was abandoned simply because it was not economically viable. not because of technical problems.

Currently uranium market prices are depressed by the effort of the US government to burn up the U235 and Pu239 left over from cold war weapons. Until that stock is drawn down their is virtually no need for new uranium. The only US uranium enrichment plant currently in operation, operates at far less than full capacity. In fact. it only operates at all because a US government owned utility, TVA buys enriched U235 from it. This arrangement has probably been made for national defense purposes. Until the weapons stockpiles are burned up, there is no incentive for more uranium or thorium explorations, reprocessing, or breeding.

The argument that we are running out of Uranium/Thorium resources, amounts to an appeal to ignorance, since it is arguing in effect that undiscovered resources do not exist, and that other fuel cycles cannot be used.

After my limited meta-research several months ago I noted breeder reaction as a sound, experimentally-validated theory, but with some significant obstacles between now and when we can have it in widespread production. I’m going to have to go back and refresh my info.

Regarding the viability of scaling up uranium (or thorium) extraction, I still wish there were studies discussing it in quantitative lifecycle (energy ROI) terms. Without something tangible to point at, it could just be pro-nuke propaganda that has as little foundation as the “50 years left” anti-nuke crowd. I don’t doubt that the elements are plentiful, I just want to know how the economics and energy return changes when we run out of low-hanging fruit.

Thank you again for your thoughts!

Uranium is ubiquitous on the Earth. It is a metal approximately as common as tin or zinc. Talk of uranium scarcity by those opposed to nuclear power is really nonsensical – it’s all around us. It just needs a commercial incentive to exploit it. This is at the root of talk about uranium shortages; the market, despite some speculative pressure of late, is not there to support all but the most economic deposits. In fact the current bump in prices were the result of the existing refined inventory surpluses being drawn down, not a drop in production.

From the outset the basic attraction of nuclear energy has been its low fuel costs compared with coal, oil and gas fired plants. About half of the cost at the current price of UO2 is due to enrichment and fabrication of fuel pellets, and these costs will remain stable even if the price of U3O8 rises. Thus the fuel’s contribution to the overall cost of the electricity produced is relatively small, so even a large fuel price escalation will have relatively little effect. For instance, typically a doubling of the uranium market price would increase the fuel cost for a light water reactor by 26% and the electricity cost about 7% whereas doubling the gas price would typically add 75% to the price of electricity from that source.

However even if raw uranium prices increased by orders of magnitude and currently unexploited known deposits were not able to meet demand, there is still a huge amount of fissile material left in so called ’spent fuel’ that can be extracted by reprocessing. This is a well known process, practiced all over the world particularly by countries like France, Britain, and Japan which do not have secure domestic supplies of yellowcake.

Thorium, which is much more abundant than uranium can also be use a fuel in some existing reactors like the CANDU-6 without modification. Breeder reactors too are existing technology that can produce unlimited amounts of plutonium that can be burnt as reactor fuel in existing designs. In fact the reason attempts to commercialize these two cycles have failed was that uranium was just too cheap.

The point here is that fuel cost and availability now or in the long term, is the least of the problems faced by nuclear energy. The arguments put forward that this source of energy should not be exploited because it is not sustainable into the future are without factual or logical foundation.

Your knowledge of case law here (some) is probably greater than mine (very little) so I won’t debate where on which way individual cases have gone. If they are being judged more “right” than wrong in the US, then huzzah; one thing less to worry about in that locality.

Now should we talk about how creationists are trying to turn school classrooms into a free speech issue? I may make a post about that in the future anyway.

A better example might be the majority enshrining certain speech above others, despite its clear conflict with other inalienable rights. “In God We Trust” comes to mind, or the “under God” portion of the Pledge of Allegiance.

In any event, I’m just being petty. Sorry.

Let’s replace the example with defamation, or other exception to free speech.

Hateful speech is still protected by the First Amendment, but not if it incites violence. That same standard is applied to speech of any form. The qualifier “hate” does however make a difference when prosecuting crimes proceeding from that speech - that is, the punishment is more severe.

For example, the KKK and the neo-Nazis are permitted to assemble, stump, publish, distribute, and otherwise express their views that anyone without white skin is inferior to them. However, the punishment against them if violence occurs is greater. Thought it might chill their speech somewhat, it seems quite reasonable to me because the characteristic of that speech is to incite such violence, and history has shown that it has been successful at it. Thus, it provides an incentive for them to be more careful about what they say, because it can so easily lead to other problems.