Those are meant to be repeat signs, by the way.
A commentator writes on this post:
It would be interesting to read your views on what science is.
It's clear what is going on here, with this comment. Consider: Person decides to examine exhibit A. Exhibit A is mainstream economics, purporting to be a scientific theory well-grounded in evidence. Person looks at exhibit A and critiques it. Person can do so on many different grounds, obviously, but one of the most important methods is through the observation that something about exhibit A is logically inconsistent, according to the laws of science (i.e. according to what we actually see in the world, or according to the logic of the theory).
Unfortunately, by doing so, Person is implicitly using a set of his own standards (namely, those of "science") in order to judge the "scientific nature" of exhibit A. But science is not an objective concept in economics or in any field because political ideology also defines what "mainstream economics" is. The question thus arises: maybe Person himself has flawed standards of what "science" is! Perhaps even MORE importantly, perhaps Person's faith in scientific reasoning is representative of a person's faith in a politically charged "idea" of science itself! Fortunately, the main point of my criticism is not to judge exhibit A against what I purport to be "objective" standards of economic science. But I need to explain this a bit more.
Still -- touché. Good point. I should not be simply saying that "Mankiw's text does not hold up to the objectives of science", because that would be saying that if economics were more scientific, everything would be fine. But of course it wouldn't be that easy, because there is a component of ideology to the study of economics!
Fear not reader, I dare not go down the path of holding Mankiw up to standards of science which I myself do not believe in. And actually there are a couple reasons for that. First of all, it's cheap. Mankiw is a textbook! While there are of course some basic standards of logical rigor to which we all must tie ourselves, textbooks are not AER articles and therefore I am not going to pick on Mankiw for small slips in logic.
Second, and more importantly, is that I need to outline my full thesis as a process of steps so people don't jump on me for things I never meant to do in the first place. That is, the extent of my analysis is meant to go much further than simply making a point about logic or rigor. I plan to do the following:
- Examine the discussion of welfare economics
- Make some observations about how Mankiw tells his story, making note of both major and minor logical slips along the way.
- Wrap it up by thinking Seriously about the overall picture of general equilibrium that the student walks away from after reading this section
- Consider the political achievements attained at that point
In other words pointing out the non-rigorous nature of Mankiw's style is not the main point of my argument. However, I do think it's important to think about how welfare economics can be taught correctly, that is, in the sense that each proposition follows from prior assumptions and propositions. But that is not because I see any intrinsic value to the logical consistency of the welfare economics model. It's because of what the welfare economics model purports to be. That is, I would like to stress its political significance in the realm of economic thought.
Here's the clincher: That last point is very crucial to me because welfare economics is really a great political achievement. I don't think you would deny that, would you? The welfare theorems are really the epitome of the utopian vision of capitalism, a point expressed in numerous commentaries on them. Thus, by subverting the logic of the welfare theorems, as Mankiw does, he really is making a great political achievement.
He's essentially subverting the political overtones of them, which is essentially political indoctrination in disguise! For another example of the subversion of the political ideas, consider what happened in the 1940s and 50s with the mathematization of the welfare theorems -- that itself was a subversion of the political overtones because the mathematics is meant to bring the whole thing to a class of Higher Truth shared with mathematics and logic.
And this all goes back to my previous post regarding Lerner's verbal run-through of the general equilibrium model (for two people) in the 1930s. In that post I attempted to argue that the reasons why Lerner brought up the discussion of the way a perfectly competitive system would work with money was not necessarily in order to provide any substantive logical critique of Marxian economics; rather, the point was a political jab. All along.
Really an amazing story if you think about it, but you can trace these kinds of stories throughout the history of non-Marxian economic thought.