Coordination problems¹ are hard to solve. We know this, but how can we use that to make money?

Well, a classic coordination problem presents people with a choice between conforming and defecting. You pay a small cost for conforming, and a large cost for defecting unless all the other participants defect as well. Structures with “network effects” behave like this. If you leave but everyone else stays, then you suffer from being excluded from the network; but if everyone leaves then you’re not going to miss out on the latest gossip/music/gerbil video.

So, a recipe for exploiting coordination problems goes like this:

• Make a network
• Encourage people to join
• Unilaterally impose a small cose for participating in the network

Then members are faced with a choice between paying up (and retaining the network benefits) or leaving - which is only profitable if everyone else does the same.

In modern parlance, this translates to:

• Start a social media company
• Offer it for free to get users
• Start charging once you have a lot of users

I think this makes partial sense of the otherwise baffling mania for startups with no revenue, but a large user-base. What they sell is not a revenue stream, but a network of users who are ripe to be extorted via this sort of coordination problem.

[Content warning: spoilers]

So… Jupiter Ascending is pretty crap.

I say that as someone who is quite willing to take a ridiculous action film for what it is. Sometimes I go to see a film for the special effects, and I understand that the paper-thin plot is just window-dressing for some really large explosions. But Jupiter Ascending somehow manages to not even clear that bar.

Why are many threaded comment systems so bad? It seems pretty clear to me that you need a couple of things to have a workable threaded comment system:

1. The ability to present long sequences of replies in a readable fashion.
2. The ability to collapse comment threads.

If you lack either of these, comments threads become horrific if you accumulate more than a few comments. As an example of abject failure, consider the comments on Wordpress blogs.¹

You can have precisely three replies in sequence before all comments are shown at the same level (destroying the replied-to relationship), and comments are squashed to fit into ever-smaller portions of the blog’s column-width, which makes long chains of replies truly long in terms of how far you have to scroll to get past them.

Consequentialist moral theories locate the good in the consequences of our actions. Naively, we might think that this then removes any sensible way of juding persons - the only thing that matters is what they do. But that’s simplistic. After all, our personal qualities affect how we act.

Most of us wouldn’t think twice at stopping briefly by the side of a quiet road marked with a double-yellow line. But will your self-driving car be of a similar mind? The car’s decision-making software is likely to be subjected to a great deal of scrutiny, especially if evidence of law-breaking is ever found. So it’s safer for the programmers to simply make it extremely reluctant to even bend the law.