Book of the Day — The Hidden Half: How the World Conceals its Secrets

Another approach to explaining why we know less than we think we know would be to invoke human irrationality or cognitive biases: the limiting effect on our understanding of the systematic ways that we distort or frame reality which lead to misjudgement and error. These undoubtedly play a part, but I will largely ignore them. That’s partly because cognitive biases have already received much excellent attention. But I also have a mild doubt about the current emphasis on people’s cognitive limitations: that it might suggest all we need do to overcome them is become a little smarter — which if you’re a reader of books about cognitive bias of course you will be. Whereas if — as I argue — a large part of the problem is an obdurate property of the world at large, rather than (primarily) in other people’s psychology (not ours, we’ve read the books), then flattering ourselves about our own exceptional genius will get us nowhere. People do take mental shortcuts, and they do go wrong, and although this is undeniably a problem partly to do with our own thinking, one reason that we take shortcuts is the sheer complexity of what we’re grappling with. The nub of a problem is often out there, and insurmountable. You could be the rational paragon of philosophers’ dreams and still be not one jot closer to discovering why the marmorkrebs are so different. So, although it may be true that we’re riddled with cognitive faults that mean we don’t see the world as it is, we have to ask to what extent this world is so irreducibly awkward as to be beyond even the most rational understanding. At any rate, we should think harder about the nature of its awkwardness.

— Blastland, Michael. The Hidden Half: How the World Conceals its Secrets .

Everything we don’t know

This sets the theme for the book, which is about the limits of knowledge, and hence the need for caution in acting on knowledge. Successive chapters look at the replication crisis in science (bound to hit economics eventually), the limitations of medical treatments, the way reasonable, intelligent people can draw opposite conclusions from the same set of undisputed facts — in short, it’s a mediation on expertise and its role in decisions. The message from the multiple examples is that expertise isn’t all experts claim it to be.