Let's say you ran the Consumer Product Safety Commission, and you were wondering whether to impose a new regulation on the makers of a pretty dangerous product. It's so dangerous, in fact, that according to your information, ten people chop off a finger with this product every day just in homes, with lots more amputations happening on the job. It turns out that there's a piece of technology that when added to the product makes finger amputations impossible. But adding this technology to each product imposes a not-insignificant cost. How do you figure out whether to impose the regulation? It's not an easy calculation, and a simple adding up of medical costs, lost productivity, and product costs won't get you all the way to a decision. There's the human suffering involved (losing a finger or two is a serious bummer), set against the basic idea that government should regulate product design only when it has to, even if that turns out to be pretty often. It's a difficult decision. The product in question is the table saw. A few years ago, an inventor came up with a system that will stop you from chopping off your digits in a saw. It works by running an electrical charge through the blade; when the blade comes in contact with human skin, a sensor detects it and throws a metal brake into the blade, stopping it within a few milliseconds. So you end up with a cut that needs a band-aid or two, but nothing worse. He took it around to the big tool manufacturers, all of whom turned him down, both because the device would add a couple of hundred dollars to the price of their saws (table saws run anywhere from a few hundred to a few thousand dollars), and, it was suspected, because they were concerned that if they started putting them on some saws, they'd open themselves up to lawsuits for not having them on all their saws. And in fact, there has been one successful lawsuit against a saw manufacturer for not including the device, called a SawStop, on their saw. Eventually, the inventor got so frustrated he started his own company to make saws with his gizmo. Now the CPSC is trying to determine whether to mandate the inclusion of "flesh detection technology" on all table saws. As a longtime woodworking hobbyist, I can testify that table saw blades hurt when they touch you (I lack a thumbprint on one of my thumbs, from an incident that was my own damn fault). In recent years, manufacturers have taken steps to improve the safety of what is, after all, a death machine -- better blade guards, standard riving knives to prevent kickback (that's when your piece of wood rockets back at your head, at speeds that can approach 100 miles an hour). But how far should the manufacturers' obligation to prevent accidents extend? If a SawStop added $10 to the price of a product that retails for $750, we'd all agree that it would negligent of them not to install them; if it added $1,000, we'd probably all agree that was too big a cost to impose. But what about a cost that's somewhere in the middle? There are good answers and bad answers, but there is no perfect answer, which is often the case when you're trying to determine whether a regulation is a good idea or not. Conservatives tend to portray regulation decisions as quick and easy. Let the market's invisible hand (hopefully with all five digits intact) decide! But they aren't. Governing, it turns out, is really complicated.