[Zuider]

>In order to act on a claim (inaction is also an action; "avoid committing oneself to accepting" is just ornate wording for choosing inaction) one must evaluate the "probability of truth" of said claim.

There is no requirement to evaluate the truth value of an ill defined, nonsensical or self-contradictory claim. In fact, a claim of that nature may as well be regarded as being meaningless. On those grounds, it makes no sense even to speak of probability in regard to such a claim.

>Honest answer: Then I invite you to attend a consensus conference

A 'consensus conference' may do one of two things:

1) It may dedicate itself to the evaluation of rational argument and evidence, in which case it is the argument and evidence that matters, and the consensus is irrelevant.

2) Some other means may be used to arrive at consensus, in which case it may be irrational, or at the very best, unscientific.

Note that the position that OP advanced, and which you appear to be defending is that the bare fact of the existence of a consensus should be treated as primary evidence on its own. At best, a consensus is secondary evidence, a pointer to the real crux of discussion, and treating it as primary evidence is a category error which is only compounded by the air of authority implied by a consensus which adds psychological coercion into the mix.

[silverspoonin]

>There is no requirement to evaluate the truth value of an ill defined, nonsensical or self-contradictory claim.

Calling a claim "ill defined, nonsensical or self-contradictory" is already an evaluation of it's probable truth value.

> Note that the position that OP advanced, and which you appear to be defending is that the bare fact of the existence of a consensus should be treated as primary evidence on its own.

Actually, the person you responded to clearly stated: "how should I evaluate truth in a subject matter that I myself don't have a doctorate in". For someone well-versed in the area, or at least with enough free time to become sufficiently acquainted with it, going to directly to primary evidence is the optimal approach. However, in the situation described by OP, were they are limited in the amount of time and cognitive capacity they can invest, then basing decisions on such "Secondary evidence" as expert consensus is the rational approach.