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army1987 comments on Being Half-Rational About Pascal's Wager is Even Worse - Less Wrong

18 Post author: Eliezer_Yudkowsky 18 April 2013 05:20AM

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Comment author: [deleted] 18 April 2013 06:37:29PM 7 points [-]

But Fermi is also the one who said that nuclear energy was fifty years off in the unlikely event it could be done at all, two years (IIRC) before Fermi himself oversaw the construction of the first nuclear pile.

For something in the same(-ish) reference class where the pessimists turned out to be right, commercially viable power generation from nuclear fusion has been “30 years in the future” ever since the mid-20th century.

Comment author: ciphergoth 18 April 2013 08:21:04PM 6 points [-]

Everyone tells this story; I'd like to see a cite. Fusion advocates tell a different story: that fusion was always some large number of dollars away, but the dollars weren't there until relatively recently. Once the dollars arrived, a roadmap was set out and has AFAICT basically hit all its deadlines, with JET, ITER and next DEMO proceeding as planned.

Comment author: CarlShulman 18 April 2013 09:16:57PM *  6 points [-]

Fusion advocates tell a different story: that fusion was always some large number of dollars away, but the dollars weren't there until relatively recently.

Could you link to them?

Comment author: ciphergoth 19 April 2013 12:04:57PM 13 points [-]

I didn't keep links when I read these things, so this is the result of a quick Google search for 'fusion "years away" "dollars away"':

The actual reason is mainly funding. People always use the "twenty/thirty/fifty years away" comment as an insult, a way of showing how fusion (or science in general) is unreliable. The reality is that when those predictions were first made in the 1970s in the wake of the Oil Crisis. What happened during the Oil Crisis? We freaked out (rightly so) and planned to allocate a huge amount of money towards fusion research. What happened after the Oil Crisis ended? That money disappeared. Essentially, scientists were promised X billions of dollars to make fusion work, and said they could do it in a couple decades. Then that money was taken away, and people expected them to stay on schedule. Of course, fusion power turned out to be a lot more complicated than we expected. But the real reason is we simply aren't paying for it. Its not "30 years away" its more like $80 billion dollars away. http://imgur.com/sjH5r


Comment author: Cyan 20 April 2013 02:58:29AM 2 points [-]

I learned something. Excellent.

Comment author: JoshuaZ 29 April 2013 01:18:53PM 0 points [-]

Note that these predictions didn't start in the 1970s. In the 1950s and 1960s similar predictions were made with "20 years away" which is an even shorter timespan. See for example here.

Comment author: gwern 29 April 2013 06:41:15PM 4 points [-]

Your link is to Life, as mainstream a publication as you could find in 1950s. We are all here first-hand familiar with how reporters simplify, misunderstand, and misreport technical matters.

As for your specific quote: I assume you're referring to pg180, the Bhabha quote? The reporter says specifically "a controlled thermonuclear reactor" was <20 years away. He didn't say economical power, power too cheap to meter, break-even or net power, or anything. Was this version of what Bhabha said actually wrong? By 1976, was there nowhere in the world a research tokamak or something which created thermonuclear reactions under controlled non-bomb conditions? I suspect there was.

Comment author: JoshuaZ 29 April 2013 07:09:00PM *  1 point [-]

Those are very good points. The first point isn't that convincing by itself since there are other similar example statements from the 1950s and 60s (although I don't have them available off-hand), and while we do frequenly criticize reporters for misreporting on science matters, most of their statements are not very far off from what is being described. Misreporting is while egregious, a small fraction of most science reporting.

Your second point seems more persuasive. By 1976, not only were there functioning tokamaks, but there were other fusion devices also such as fusors. So the prediction of controlled thermonuclear reactors in 20 years did come true, not just for tokamahs but for other fusion methods as well. This substantially reduces the validity of my point.

Comment author: gwern 29 April 2013 07:50:02PM *  2 points [-]

and while we do frequenly criticize reporters for misreporting on science matters, mos of their statements are not very far off from what is being described

I dunno, sometimes they are completely wrong. A few days ago I got the writer of http://arstechnica.com/tech-policy/2012/06/fbi-halted-one-child-porn-inquiry-because-tor-got-in-the-way/ to massively edit the middle of the article because the original source document explicitly said the child porn was not on Silk Road... and his article said the child porn was on Silk Road. Which is about as wrong as possible. And this is far from the first example of the media getting technological or scientific things completely wrong, which is why you need to read the comments or read the original papers if you're going to base any beliefs on what you're seeing.

It's not hard to make the reported versions of stories or predictions be completely wrong, especially in the context of fusion where we were originally discussing the claims of fusion reporters that the credible published official estimate from the government report of 20-30 years were indeed real but had been made explicitly on the basis of enormous funding increases which never materialized, funding was cut substantially, and actual progress has been better than predicted by the low-funding scenarios. (I put a request in the research help page for a copy of the original report to see if the presented graph is accurate but it hasn't come yet.) It's very easy to slide from the apparently accurate version of the conditional prediction "We predict economical fusion in 30 years if we get the planned funding of $80 billion" to the version "they predict fusion in 30 years".

Comment author: Dr_Manhattan 21 April 2013 05:48:54PM 4 points [-]

SImilar story is told about fission weaponry.

1939, Nobel Prize-winning physicist Niels Bohr had argued that building an atomic bomb "can never be done unless you turn the United States into one huge factory." Years later, he told his colleague Edward Teller, "I told you it couldn't be done without turning the whole country into a factory. You have done just that."