[randalluk]

>That is the informal definition of an externality right there.

You pay a grocer who pays a farmer who pays a fertiliser manufacturer who buys some natural gas. You wanting to eat has a reasonably direct impact on demand for fossil fuels, and therefore prices and profits. The oil company doesn't capture all the value, partly because they're not doing all the work, and partly because of competition.

If the oil companies went away tomorrow, the price of oil would skyrocket, because people want to eat, and new oil companies would form to meet the demand. There is no need for subsidy.

Positive externalities are things like "I financed construction of a road for my own commercial reasons, but other people can use it for free". Or "I wanted to renovate the rundown building I live in, but doing so made my neighbour happy too".

But to come back to the point, finally. The argument is that we know crypto mining has negative externalities (crypto miners don't have to reimburse people negatively impacted by climate change). The article argues that permissionless blockchains are doomed, ultimately, to fail anyway. So they will destroy value, by pointlessly wasting fuel AND by harming the climate (which doesn't factor into a miner's decision-making because it's an externality).

[roenxi]

> There is no need for subsidy.

There is if we add on a tax for the negative externalities, we need to consider both positive and negative externalities to get the tax right. The evidence is that the more fossil fuels we use the better off people are. If we add a tax on we'll use less, which is pushing the market in the wrong direction.

It is very hard to argue coherently that less & more expensive energy leads to better outcomes. The evidence is that in countries like China, Africa & India everyone benefits a lot more from using more fossil fuels than the cost of any negative externalities. We've run a big natural experiment here, the outcome is that more fossil fuels == rapidly improving living standards. Less fossil fuels leads to poverty.

Breaking growth in fossil fuels with a tax would be doing much more harm than good, even to bystanders. So there must be a large positive externality here somewhere. Because if you reduce the negative externalities and the outcome is much worse for everyone then there was probably a big positive externality in there somewhere.

I dunno, I suppose as a question - who do you think is bearing the cost of these negative externalities right now? Because it sounds from your reasoning like you are imagining a group of people who don't use fossil fuels or sit downstream of fossil fuels (so they can't influence the market with price signals). Who are these people, demographically speaking? And to preempt my argument, would they not be better off if we got them access to fossil fuel rather than worrying about negative externalities as they sit outside the system? It worked great for China.

[randalluk]

> There is if we add on a tax for the negative externalities, we need to consider both positive and negative externalities to get the tax right.

There are few positive externalities directly associated with the act of burning oil, except some associated with global heating.

There may be positive and negative externalities from the things people choose to do with the power generated. Companies are generally better at internalising positive effects than negative ones, for obvious reasons. If my chemical plant produces hot water as a waste product, I can sell that to the plant next door or to a district heating system. Competent business try not to leave value on the table, and try not to pay costs that they don't have to. But where they can be identified, sure, subsidise away. Just not crypto mining.

> So there must be a large positive externality here somewhere

Not necessarily. There is/was a large positive asset: ie. a huge store of chemical energy underground. It has allowed us to do incredible things. If the cost of it included the negative impacts of burning it, the market would use less of it, smarter, more efficiently, towards the most valuable outcomes, and in better balance with the harms.

>who do you think is bearing the cost of these negative externalities right now? ...would they not be better off if we got them access to fossil fuel

I'm not a climate scientist and I'm not qualified to re-litigate the scientific consensus, which is that global heating is dangerous. Some will be more affected than others by increased incidence of extreme weather, water wars, mass migration, cost of flood defences etc. But ultimately it is a "tragedy of the commons": few of us are innocent, most of us are impacted or at risk in some way. It isn't even in the interests of those of us with economic power to stop polluting, because the cost of each of our individual actions is externalised. If I take a flight, I get the full benefit, but experience only one eight billionth of the total harm. That's why it needs a systemic fix.