When politics makes us irrational
I have been reading a very powerful article on the Unherd site by Tom Chivers called
"How politics makes us irrational."
It refers to two studies which are about to be published and which find that people with strong ideological beliefs - whether left or right - find it harder to spot errors of logic an arguments supporting their beliefs.
It is important to distinguish here between errors in your premises and errors in logic. Chivers starts by quoting an example of a syllogism which starts with a false premise and argues with perfect logic through to a false conclusion.
Consider the following:
“All things made of plants are healthy. Cigarettes are made of plants. Therefore, cigarettes are healthy.”
The conclusion is wrong because the major premise is wrong: plenty of things which can be made from or obtained from plants - deadly nightshade, and cyanide to give two examples - are not healthy. Tobacco is an example.
The actual syllogism is perfectly logical and if the two premises had both been right, the conclusion would be right too.
However, because the conclusion is so obviously jarringly wrong, there is a tendency to assume that the logic must be wrong too. That can be the case but in this instance it isn't.
in the first of the studies to which Tom Chivers refers, respondents were asked to rate themselves from “very liberal” to “very conservative” and then asked them to judge some ideologically loaded syllogisms such as
“All drugs that are dangerous should be illegal. Marijuana is a drug that is dangerous. Therefore, marijuana should be illegal.”
This was an American study so "very liberal" roughly maps onto what would be described as "very left-wing" on this side of the pond and "very conservative" roughly maps onto "very right-wing." This would not be an exact match.
And the results? researchers found that conservative-minded people were quite a lot better at spotting false syllogisms when they have liberal conclusions, and vice versa. It wasn’t an enormous effect, but it was significant – in one of the experiments, conservatives spotted unsound arguments about 80% of the time when they had liberal conclusions, but only 60% when they had conservative ones, and the effect was almost exactly reversed for liberals.
A second similar study found broadly similar conclusions.
I want to stress the point - neither study found any evidence that people on the right are more prone to errors in logic. To quote Tom,
"Both Left-wingers and Right-wingers find it harder, to roughly the same degree, to make accurate judgments in the face of an ideological headwind."
The key lesson from this is that it is not enough to be vigilant for the biases of others: it is important to watch out for one's own.
"How politics makes us irrational."
It refers to two studies which are about to be published and which find that people with strong ideological beliefs - whether left or right - find it harder to spot errors of logic an arguments supporting their beliefs.
It is important to distinguish here between errors in your premises and errors in logic. Chivers starts by quoting an example of a syllogism which starts with a false premise and argues with perfect logic through to a false conclusion.
Consider the following:
“All things made of plants are healthy. Cigarettes are made of plants. Therefore, cigarettes are healthy.”
The conclusion is wrong because the major premise is wrong: plenty of things which can be made from or obtained from plants - deadly nightshade, and cyanide to give two examples - are not healthy. Tobacco is an example.
The actual syllogism is perfectly logical and if the two premises had both been right, the conclusion would be right too.
However, because the conclusion is so obviously jarringly wrong, there is a tendency to assume that the logic must be wrong too. That can be the case but in this instance it isn't.
in the first of the studies to which Tom Chivers refers, respondents were asked to rate themselves from “very liberal” to “very conservative” and then asked them to judge some ideologically loaded syllogisms such as
“All drugs that are dangerous should be illegal. Marijuana is a drug that is dangerous. Therefore, marijuana should be illegal.”
This was an American study so "very liberal" roughly maps onto what would be described as "very left-wing" on this side of the pond and "very conservative" roughly maps onto "very right-wing." This would not be an exact match.
And the results? researchers found that conservative-minded people were quite a lot better at spotting false syllogisms when they have liberal conclusions, and vice versa. It wasn’t an enormous effect, but it was significant – in one of the experiments, conservatives spotted unsound arguments about 80% of the time when they had liberal conclusions, but only 60% when they had conservative ones, and the effect was almost exactly reversed for liberals.
A second similar study found broadly similar conclusions.
I want to stress the point - neither study found any evidence that people on the right are more prone to errors in logic. To quote Tom,
"Both Left-wingers and Right-wingers find it harder, to roughly the same degree, to make accurate judgments in the face of an ideological headwind."
The key lesson from this is that it is not enough to be vigilant for the biases of others: it is important to watch out for one's own.
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