[SEQ RERUN] Fallacies of Compression
Today’s post, Fallacies of Compression was originally published on 17 February 2008. A summary (taken from the LW wiki):
You have only one word, but there are two or more different things-in-reality, so that all the facts about them get dumped into a single undifferentiated mental bucket. It’s part of a detective’s ordinary work to observe that Carol wore red last night, or that she has black hair; and it’s part of a detective’s ordinary work to wonder if maybe Carol dyes her hair. But it takes a subtler detective to wonder if there are two Carols, so that the Carol who wore red is not the same as the Carol who had black hair.
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I think speaking more than one language (from distant language groups) does help a fair lot. You see how a continuum can be bucketed differently, among other things.
Other big issue is that great many people actually see a form of compression as some amazing virtue of “Abstract thought”.
That is itself an example of compression—mixing together the human capacity to create useful abstractions, to be able to make predictions about the real world by using very little computational power, with the human brain limitations that disallow fine grained modelling and which in fact greatly impede our ability to make predictions about the real world.
While it is awesome that we can describe weather in terms of different cloud types, the most accurate weather simulation is the one working at the lowest abstraction level that we have the computational power to work at—cells with air properties, the smaller the better—the division into cloud types only helps when you are pretty much incapable of modelling clouds to any extent.
I propose that one should try to think of things as non-abstractly as one can (except for very special cases where abstractions are surprisingly close to the territory). The less stuff you abstract out the less likely you are to make dumb mistake or over the chain of reasoning slowly diverge from correctness.
Are the following two examples examples of the kind of compression that the post is about?
ONE) Two meanings for Minimum Wage.
First, the government runs factories in which unskilled workers make stuff and get paid the legislated minimum. The government takes on all the workers who apply. That means that no-one need go hungry. If you cannot find a real job you can go to the government factory and get a minimum wage job. Since these factories are churning out generic stuff that isn’t much wanted, they make big losses. The losses are met from the welfare budget which comes from general taxation.
Second, the government merely forbids employment at less than a legislated minimum. There is no guarantee that work is available. Absent other welfare programs you may go hungry because of this prohibition. It costs tax payers nothing.
Call them MW1 and MW2. It is rare to see an increase in MW2 headlined as “Minimum wage made harsher.” even though the prohibition gets stricter. I suspect this is because “harsher” would not apply to an increase in MW1, and MW1 and MW2 are usually munged together in some kind of vague faith that jobs are always available at MW2.
TWO) “Government raises taxes” sometimes means that the government raises tax rates and sometimes means that tinkering with the tax system brings in extra revenue. To see the difference, think about Greece in 2011. Could the Greek government pay off its debts by raising taxes? Well, it could always raise the rates at which it levies taxes, but since the country isn’t rich enough to pay its debts that will probably just wreck the economy and reduce revenue.
The examples in Fallacies of Compression were 1)if a tree falls in a forest and there is nobody there to hear it, does it make a sound. 2)Are the trees leaves in the same place, it sure looks that way from the map? 3)You mean there are two Carols! They are nice examples, and serve the purpose of basic exposition well, exactly because they steer clear of politically fraught areas.
Nevertheless, I’m left wondering if I’ve grasped the point correctly. If I try to recognise a Fallacy of Compression in the area of political speech does my mind get killed? Do my two examples serve as 2nd level exposition, showing why we care about fallacies of composition?
I think a large part of mindkilling is that in political discussions most people make extreme compressions—like compressing hundred ideas under one label. Also different people compress different things under the same label, and then they argue which one’s usage of the label was the right one.
If one hopes to talk about politics rationally, one must uncompress, uncompress, uncompress… but then they are usually no longer talking politics (as it is usually understood), but economics or sociology or something else.