Type of false reasoning?

Question

I don't have extensive background in philosophy but I try to outline my question clearly.

I am arguing with a person who always uses the same logic.

We have an outcome X such a medical disease prevalence. Then we observe an effect in X such as increase in prevalence.

Compelling evidence shows that change in X is due to cause A. However this person says that change is due to B. He also continues that I have the burden of proof to show that effect CANNOT be due to B before we can accept A. Almost non negligible evidence is enough to support this person's view about B as the cause.

In similar fashion I could say that effect is due to climate change or Jupiter's moons if I followed this person's logic. So my question is that is there an official definition of this person's false reasoning?

Answer 1

The concept of a "burden of proof" is often misapplied. If you believe something, then you have a duty to justify it, no matter what it is. If you think A causes an increase in X, you do have a duty to provide evidence in support. If your friend thinks B causes an increase in X, they have a duty to provide evidence in support. There is a burden of proof on both sides.

The burden of proof is most often used to say that an unusual claim, one that departs from the norm, needs more evidence in support. This is true; an a priori unlikely claim requires more evidence, in the Bayesian sense, to raise its probability close to 1. However, it can only be applied if both participants in the discussion agree on what the norm is. Clearly, the two of you do not, so if either wishes to persuade the other then they have a burden to produce strong evidence in favor of their claim.

We might say that the basic problem is that your friend is not trying to persuade you, he's trying to affirm his own beliefs. From his perspective, "B causes increase in X" is the norm, and any departure from that norm would require a lot of evidence to change his own mind, so that is why he says you have a stronger burden of proof. It makes sense to him and affirms what he already thinks. But it is completely ineffective at persuading you, because you have a different norm, and from the perspective of this other norm, "B causes increase in X" is the departure that requires more evidence.

So, he's probably not trying to persuade you, he's just trying to make himself feel better about his own views. And that's the problem. In a discussion we should try to make arguments that appeal from the other person's perspective, not just our own.

See also this SMBC comic.

Answer 2

That kinda hinges on how much you assert this to be true:

Compelling evidence shows that change in X is due to cause A.

Like if that causes you to say that "A is the cause of X", then you'd likely be the one committing a fallacy here, because you're making a statement of fact from an inductive argument. While inductive reasoning is only able to create strong or weak arguments, but none that are true or false.

Classic example would be that you're watching birds and all the swans that you've ever seen had been white and you've seen a lot, so you conclude that all swans are white. Which from your point of view is a reasonable argument given the evidence that you've seen a lot and are some kind of expert in the field. Problem is black swans do exist. So the statement "all swans are white" is wrong even though it's probably a very useful statement (for Europeans) and holds most of the time (for Europeans).

So with inductive arguments you can't really make conclusive statements like that, but can only conjecture based on evidence. Which is also why science is pretty much always "wrong", but it matters a whole lot how wrong it is. Like you could miss your estimated target by a fraction of an atom or idk a lightyear.

So if you say A is the cause, then one counter example or alternative solution would suffice to say that there is still doubt and you'd commit a fallacy by stating that A is the cause of B. So if that would indeed be your claim, then yes it would suffice to state that alternative and it would be your job to disprove it. (Within reason), like if B is "and then god interfered" then you'd be sent on a whole different errand trying to prove or disprove god where it's usually considered the other person's burden of proof to at least give some non negligible reason for why that could be the case to begin with.

Now what that doesn't conclude is that if it is not A than it must be B. It could very well be not A and not B so unless you can prove that there is a binary (idk B being not A) then there could be any number of alternatives to that.

Also in case you're not making the mistake of claiming with certainty that it must be A, the other person might commit the fallacy fallacy, namely that just because you're making a fallacy to assume that it is certain doesn't mean that it can't be true in this specific scenario (just not as a general rule, all the time).

So are they actually using that as evidence that B is true (or more likely) or do they just use it as an alternative to A?

Also depending on the circumstances you might value Type I and Type II errors differently, that is the rejection of the hypothesis even if it were true or accepting the hypothesis even if it were false.

Answer 3

You have presented no evidence that your opponent's reasoning is false and your is true. You have only explained why you believe it to be specious. The language of explanation is distinct from the language of the argument itself. The best way to approach the discussion is to have a discussion about where you differ on the particulars of evidentialism. From WP:

Evidentialism is a thesis in epistemology which states that one is justified to believe something if and only if that person has evidence which supports said belief.1 Evidentialism is, therefore, a thesis about which beliefs are justified and which are not.

You claim your adversary invokes bad causality, but your adversary claims yours is the bad causality. As you have presented no arguments of causality strictly speaking, anyone who presumes you are right and your opponent is wrong has missed an important point: we all are capable of bias; that all of our knowledge is fallible (IEP).