In the late 19th century, two researchers meet to discuss their differing views on the existential risk posed by future Uncontrollable Super-Powerful Explosives.

• Catastrophist: I predict that one day, not too far in the future, we will find a way to unlock a qualitatively new kind of explosive power. This explosive will represent a fundamental break with what has come before. It will be so much more powerful than any other explosive that whoever gets to this technology first might be in a position to gain a DSA over any opposition. Also, the governance and military strategies that we were using to prevent wars or win them will be fundamentally unable to control this new technology, so we'll have to reinvent everything on the fly or die in an extinction-level war. There's no way we'd be competent enough to handle something of that power without killing ourselves almost immediately.
• Gradualist: I’m also concerned about the prospect of explosives one day becoming far more destructive than they are now, with possibly catastrophic consequences if we aren't prepared. I'm not so sure that we’d instantly go extinct if you were right, though I agree that if anything like what you're describing is real, we’re in a great deal of danger. But we'll leave questions of Governance for another time. In the meantime, I want to push back against the idea that this will all happen so suddenly. What does that word 'DSA' mean?
• C: Decisive strategic advantage. Anyone who has that technology would be able to render any military opposition irrelevant. Probably, they'd be able to wipe out entire cities with one bomb and force their opponents to surrender almost immediately.
• G: That seems like a weirdly specific prediction to make. Why assume something so unlikely? Have you got any evidence such a thing is even possible?
• C: I have my reasons, but first let me deal with what you just said, because I can't let that slip. Zero-to-one discontinuities are actually pretty common in the history of technology. Someone had to invent guns or steam engines for the first time. Why wouldn't there be a zero-to-one transition for explosive power someday?
• G: Because zero-to-one discontinuities happen when you do something for the first time.
• C: Yes, that's what I'm suggesting.
• G: No you aren't: we've already had our zero-to-one discontinuity! We've invented black powder, then dynamite and fuses, from now on there'll be incremental changes and inventions that increase explosive power. We might see step changes when some new kind of chemical is discovered, but what you're talking about isn't possible. Or it's at least highly unlikely.
• C: Why? You’ve just admitted step changes happen all the time.
• G: Because what you're talking about requires people to just ignore a hugely promising road to technological improvement, probably consisting of many steps, for ages, to get so much of a lead over their competitors in explosives technology.
• C: And who says that explosive power actually works like that?
• G: Because that's our default expectation with a technology like explosives, where there are lots of paths to improvement and lots of effort exerted on every part of the problem. Unless, you maybe have evidence that this isn't how it works?
• C: Yes, I was just getting to that. Your priors don't mean anything if we have already seen an existence proof for qualitatively new energy sources.
• G: So you have a design for this super-explosive?
• C: No, but that’s not necessary for my point.
• G: So you've at least found a new principle of physics that implies it is possible?
• C: I'm talking about the Sun. The energy the Sun outputs is overwhelming, enough to warm the entire earth. One day, we'll discover how to release those energies ourselves, and that will give us qualitatively better explosives. I can't say how to do it of course, other than maybe giving you some vague hints about replicating the conditions inside the sun, but to be honest I don't really expect our super-explosive to look much like the Sun, any more than trains look like horses. All I know is that it will use the same underlying principle that the Sun uses to release its incredible power.
• G: How does that get you to assuming there'll be a discontinuity?
• C: Because not getting a discontinuity when we discover the power of the Sun would require an extreme coincidence.
• G: How can getting that incredibly specific outcome of a massive jump in capability be the default?
• C: The Sun is an existence proof for the new kind of explosive energy. And we know that under the right circumstances this energy can exceed our best regular explosives by a vast amount, so it seems foolhardy to assume our first super-explosive will just happen to be as powerful as our best normal explosive technologies are whenever we make the discovery. Why would that be the case?
• G: Oh, I see. Well the flaw in your argument is clear then. You're assuming the Sun is something qualitatively new.
• C: You think it isn't? I'd like to see you pile together enough TNT to heat the Earth.
• G: The idea that there'll be a 'first person to discover the power of the Sun' is a mirage. I offer a micro-foundational explanation of why the Sun seems like a qualitatively new energy source, but really it isn't.
• C: Let's hear it, then.
• G: I think that the Sun is nothing but a giant ball of gas heated by gravitational potential energy. One day, in some crazy distant future, we might be able to pile on enough gas that gravity implodes and heats it, but that'll require us to be able to literally build stars, it's not going to occur suddenly. We'll pile up a small amount of gas, then a larger amount, and so on after we've given up on assembling bigger and bigger piles of explosives.
• C: Why assume that's how the sun works, and it's not something new? Do you have any evidence for your view?
• G: This is compared to the view that the sun is powered by something entirely new and unknown?
• C: New, maybe, but it's not unknown. Just look out of a window.
• G: I don't have any specific evidence that it's powered by gravitational collapse, since my model was made to retrodict observations we’ve already made, but your theory explains the same phenomena more vaguely while making a bunch of extra assumptions that we don't need. I can already provide a somewhat satisfactory explanation, even if a few details don't make complete sense yet, like the age of the Earth. So you might be right, in principle. I've not checked my maths on this model that thoroughly.
• C: I think you're overly confident in your gravitational collapse theory because it fits your priors about 'smooth progress', even though it’s only a vague match with observation. My theory that the Sun is powered by something different is a much more natural explanation.
• G: I'm still not seeing any good evidence against my view, though. And I even grant that you don't have literally zero evidence in favour of your view, from the existence of the Sun. (Though I note you’re also retrodicting things we've both already observed). Something like the Sun existing is somewhat more natural if you assume there's some incomprehensible physics secret powering it instead of gravitational collapse, but I can't seriously credit your world-view much beyond that otherwise.
• C: I'm working on a proof that the Sun can't just be heated by gravitational collapse.
• G: I’d like to see that. In the meantime, let’s see if we can find out if our conflicting theories about the Sun predict anything different that we can test right now. That’s probably the best way to move this forward.