Well, that's the problem to solve, then.

1) Make it less difficult to learn - this is only a matter of investing in producing good teaching material and making it easily available.
2) Make the idea of mainframes much more appealing. There's loads of stuff in a mainframe and even in z/OS, that is way cooler than the average PC crap.
3) Make it legal for people to download and run z/OS etc on the Hercules emulator for development and study purposes after a similar model like Oracle's

People have taught themselves Linux and Windows, not because it is more interesting, really, but because it is much more approachable; and within the reach of a tight budget. Which teenager is going to invest tens of millions in a mainframe? Make it free, like Oracle did with their database - it worked for them.

- and give the user something they actually want or need. The smartphone is popular because it is flexible enough to cover a wide range of needs that people have, not because it is cool or "wearable". In fact, I suspect that being wearable often counts against a device, because it so often has to be worn in a highly specific way, unlike a phone, which you just stuff into a pocket, bag, glove compartment or whatever.

why they don't just sell their spent fuel? It shouldn't be difficult to find buyers in, say, the Middle East.

Yes? That is of course not right - anecdotal evidence is valid evidence, but one anecdote is not enough evidence to either support or reject a theory. My postulate, if you will, is that is we collect all anecdotal evidence and review it without bias, what we will see is that:

1) There is a growing trend towards more unusual or even extreme weather, and
2) Overall, there will be more anecdotes about unusually warm events than about unusually cold ones.

There, I have now put forward two predictions; if you want to be scientific about it, go and find evidence to falsify them. It is a large undertaking, of course, but it is something most people with access to Internet, libraries etc can do if they want.

Really? Do you happen to know their names and what their branch of science is? And BTW - what is "many"? You are simply postulating vague nonsense without quoting any evidence; unlike the real scientists, who are specific and quote evidence.

As for fear mongering - what you guys are saying is "Look, they want to take our cars and our modern lifestyles away and make us poor"; is that not fear mongering? In contrast, the scientists are not spreading fear and despondency like you; they say it is possibly to avert much of the harm if we work on it, and they point out that we can, in fact, benefit economically from doing so. How is that 'fear mongering'?

Finally, explain this: Many, if not most people of my age (55) in northern countries can remember how, in their childhood the winters always seemed colder and with more snow; now, in N. Europe winter seems more like an extension of autumn. I have seen flowers in February that I remember from late May when I was a child. And so on - there's even large flocks of wild parakeets living in many parks in London now, fig trees thriving and in one place, on the A40 near Ealing in London, there's even a date palm.

Ironically, most Americans (apart from the relatively few Native Americans) were foreigners not long ago.

I can't claim to understand bitcoin (or virtual currency in general), but as far as I can make a mildly educated guess, the value stems from the fact that the work required to produce them is so great that it has to be a collective effort. If it somehow becomes easy, then they are no more than a form of pyramid scheme.

Other currency standards are based on things of tangible value - even gold or diamonds have a practical value far beyond being pretty. Bitcoins, on the other hand, have no intrinsic value - we could wipe them out completely today, and the world would be no poorer in real terms.

As always there is a lot of noise about this, as if it was possible to determine the truth by shouting the loudest. People seem to forget that this is SCIENCE: it means that the scientists are saying "These are our data, we think it means so and so" - and then everybody can in principle go away and check and draw their own conclusions. A lot of very competent people have done exactly that and reached conclusions very similar to the IPCC, and they can argue very convincingly for the validity of their calculations.

I have not, on the other hand, heard any of the so-called sceptics do the same - which is probably why they direct their arguments at the general public, who are not in a position to actually question their explanations. Let the sceptics present their data, like all real scientists do; if their data and their conclusions are valid, then they will stand up.

Ah, but of course, this is where the conspiracy theories set in: You can't get funded, you can't get published etc, and it is not because you are wrong or your research is flawed - no it is the fault of The Establishment of Evil Scientists, who make a career out of milking the research funds dry. Yeah, right.

*Sigh*

The comments on this list really show America in a very unflattering light, sometimes. Fortunately I and many others are less superficial, so I know that most Americans are not complete idiots.

How about reading the article with a more open mind? It is after all about something that is a good idea: using some quite simple, cheaply available technology to do something that is potentially good for the environment. And while judging how poisonous smoke is by looking at it is not accurate, it still gives a reasonable indication in most cases: black smoke is probably full of particulates, white smoke is perhaps mostly steam and so on. It's not as stupid as you make out.

Can it be used for spying? Well, obviously - but it can also be used for billion good things. And as you say in America: "Guns don't kill people ...". It makes little sense being opposed to a technology for what it might be used for by bad people.

In that case, the obvious thing is to execute the person, quickly and cleanly. Vengeance will never make sense - not only is keeping a prisoner in this case extremely wasteful of resources that could be better spent elsewhere, but it also doesn't allow the families of the victims to move on with their lives. I know very well that it sounds very cynical to anyone that's weighed down by sorrow, but the only way to get better is by moving on; holding on to the suffering is only misplaced loyalty and it can not bring the lost ones back or undo what has happened.

Hmm, interesting viewpoint; I advocate moderation and talk about being willing to take part in society and take on the responsibilities that come with freedom - so I am a "filthy parasite". And you offer no arguments that I can discern, so my views still stand unchallenged. I present my views logically, thus inviting everybody to contradict me; all you do is howl incoherent abuse. Who of us stands out as the better person, do you think?

I won't claim to have to ultimate solution, but perhaps something along similar lines as apprenticeships might work? Ie. while you study, you earn a modest, but adequate salary in return for doing work that is relevant to your studies.

It is no wonder that young people are less and less interested in studying at university. I don't think it is only about debt - it is debt, combined with the feeling of seeing your less gifted class mates getting an apprenticeship, then job, family, car, house and going of on holidays every year, while you are still struggling with debt in a job that perhaps only just pays more than the average plumber makes. And to top it off, you find that you are regarded with something rather like contempt in the wider society - you are "a nerd", and there's all the tired jokes about graduates only being able to find a job in McDonald. Being intelligent and well educated is something that increasingly feels like low-status, and definitely not attractive. If society genuinely needs people to bother with education, then these things have to change.

Every time this subject comes, there is howl from the Americans about "freedom", as if people on /. knew what it is. There are several reasons why this leaves me feeling a bit nauseated - let me just recount a couple:

1. I am old enough to have lived through the Vietnam years. I have read about the McCarthy era, and I believe we have all seen the Iraq wars. I remember how America was one of the staunchest supporters of South Africa under apartheid etc etc. As far as I can see, freedom to American is mostly a matter of convenience; you guys seem all out for freedom and the right to free speech, when it doesn't really cost you much. Yes, I know - I'm being harsh, and probably too much so, and I shouldn't generalise, but Americans in particular need to shut up and think before spilling their guts about "freedom", just once in a while.

2. Words like "freedom" and "censorship" are highly charged, and they are mostly abused as a cover-all and an excuse for why it is OK to be a filthy parasite on society. So, when you roll out "freedom" as your argument without qualification, it is 99% likely that it just means "I don't want to give up my ...." (substitute "porn" or whatever it is this time).

3. There is no such thing as absolute or perfect freedom. There will always be rules and limitations, and most of them you don't even want to be free of, if you were to think about it. The best anybody can hope for is enough freedom to feel happy about your situation and your prospects; and that is not really all that much. You want to feel that you can speak openly without fear, and that you can choose to pursue your own happiness in the way you see fit. Most people don't really want to be free from social context, even if they say so - as the song says "Freedom's just another word for nothing left to lose".

4. What you see as freedom may feel like slavery to another person. Take the stupid furore in Europe about whether muslim women should be allowed to wear a burqa in public; if you ask themselves, they actually want it in most cases, but no, no, they have to be forced to accept our kind of "freedom". If you don't see the flaws in that sort of logic, then I'm afraid there is no helping you.

I am all in favour of allowing people freedom, and think it is best to avoid banning things in general, but true freedom starts with respect for others.

I'm not convinced. What you really need, in order to teach a difficult subject, is understanding of why it is difficult to understand for an initiate, and I suppose somebody who has just learned may be much closer to that understanding, but on the other hand, you also need a very thorough understanding of what the subject is all about, and you probably only get that with experience. I think what would really make a great teacher is somebody who has long, practical experience of what the subject is used for and who really enjoys answering questions.

What you fail to appreciate is that "species" is an abstraction - a useful tool when you classify living creatures and a great aid when you communicate with your fellow biologists, but there is nothing stopping you from classifying your ant species according to the shape of their left foot or whatever.

So, the split into distinct species is more a question of what we can agree on; the common criterion is that they are distinct species when they can not produce fertile hybrids, although this is not always strictly applied. The question of why two populations of the same species drift apart, this is something has been the subject of much scientific treatment - I think the consensus is that it starts off when the two groups stop interbreeding for whatever reason, and the natural changes that accumulate over time make them "drift apart" until they can be considered separate species.