The commenter on Ed Brayton's blog didn't like being called a nincompoop (although I'll say once again, I was referring to only one line in an otherwise intelligent comment). He responded, in part:
Ecologists and engineers don't take economists seriously.
That point deserves discussion because, as a friend of mine always says, "it's so wrong in so many ways I don't know where to start."
So let's begin with the fact that this is a blanket claim about all ecologists and engineers. Does this person really expect us to believe that there are no ecologists and engineers who take economists seriously? I want to see documentation on this. Has he done a study? Is there actual data to support this? Somehow I doubt it.
Then there's the "so what" factor. This is just an appeal to (questionable) authority. Are ecologists and engineers necessarily well-educated in economics? That is, do they have the expertise to make an informed opinion on whether to take economics seriously or not? Or is s/he just assuming that all ecologists and all engineers are more knowledgeable about all things than all economists are? Nobody is qualified to talk knowledgeably about fields in which they have no training.
Finally, there's the delicious irony that engineers and ecologists (whatever individual ones may think about economists) work in fields where economics is crucially relevant. We'll start with the easy one, engineers. First we need to define what economics actualy is. Here's a nice succinct one:
1 The study of choice and decision-making in a world with limited resources.
The important implications of making choices about how we use limited (scarce) resources is that we have to choose between competing uses of them. We want, ideally, to choose the option that gives us the greatest benefit for the least use of resources. Therefore, economics is the study of cost/benefit analysis, as much as anything else.
How does that apply to engineering? Let's say I'm designing a bridge. If resources were not limited I could just build a massive bomb-proof, earthquake proof, even meteor-proof edifice. But in a world of scarce resources, that would be a waste--the extra resources (not just material ones, but also time and labor) that went into could be better employed elsewhere. Engineers are masters of cost/benefit studies--they want to use minimum materials to achieve their design goals. If you find an engineer who says cost/benefit analysis doesn't matter, you can figure that he also means the cost you pay and the benefit you receive doesn't matter, so don't hire him!
OK, that was easy. But what about ecologists? Not quite so obvious, but economics still apply. A colleague of mine in my college's Biology department studied imported red fire ants for his Ph.D. work. He asked me to read a paper he was trying to get published (he was successful), and I noticed that he was looking at the ants' nutrition loading in relation to the distance they had to travel to access those nutrients. He explicitly discussed it in cost/benefit terms, and if I remember correctly he even referenced an economist in explaining that part of his research.
He's not precisely an ecologist (his specialty, as you might guess, is entomology), but he was looking at the relationship between ants and their environment, which is ecology. And very simply, animals that thrive and reproduce successfully are the ones that master (even if its instinctive) their cost/benefit ratio in interaction with their environment.
Consider a simple model, where we assume an animal with only two behavioral options, eat or screw. Let's further assume--just because I like the example--that it's spring in Yellowstone National Park and the animal is a bison bull. If you've ever been there in spring, you might notice that the bison aren't especially aggressive then, all they're focused on doing is eating. The relevant facts are (1) that they've just gone through a harsh winter with little food availability and they now have only a few months to bulk up, and (2) the cows aren't receptive for mating until fall. Now imagine some bison bull looking around and thinking, "Hey! Nobody else is going after those females! Now's my opportunity!" So he spends all spring and summer chasing cows instead of eating. He fails to reproduce then (because the cows aren't receptive), and when fall comes he's too weak to compete for them. And of course he goes into winter without adequate fat and dies before next spring. Now if you don't think that's a cost/benefit issue for bison because they're not making reasoned choices, you're a bit slow. Natural selection will favor those who make the best choice of resource use, and their offspring will come to populate the ecology, rather than those who make poor resource choices. That is, evolution will favor instinctive behaviors that have the same results as wise cost/benefit decisions.
So, ecologists don't take economists seriously? I'm willing to predict that the good ones do.