Something I posted on Seth Roberts's blog:

I like this term “twisted skepticism”. It’s more palatable than “dishonest skepticism”.

Justifications for the habit of twisted skepticism, and for specific examples of it, always sound plausible, but are often revealed as rationalization when the same individuals fail to be similarly skeptical of ill-supported notions favored within their community. E.g., no astronomer can remain in good standing while expressing any skepticism that 98% of the universe’s mass/energy is composed of stuff of which no hint has ever been detected in a laboratory. Likewise, none may be skeptical of the faith that gravitation must be the entire explanation for any large-scale phenomenon, or that the Doppler effect must explain all observed red shift, without exception.

Different fields of science have different levels of dogmatism; astronomy’s may be higher than most, paleontology perhaps lower.

I have identified two systematically irrational behaviors common to scientists. First, there is commonly an established theory which is inconsistent with new data. (Perhaps no diagnostic data ever supported it; it may have originated as an honest speculation by a respected elder.) An alternative theory is simpler, accounts equally well for old data, but also predicts the new data. A rational scientist would accept that there are now two theories on possibly equal footing, but this never happens. Instead, the new theory must pass overwhelmingly more stringent tests than the old theory ever did before it may even be considered as a reasonable alternative. Until this occurs, the contradictory data is ignored or discounted.

A related systematically irrational behavior occurs when new data conclusively falsifies a commonly-held theory (or received speculation), but no one has advanced a palatable alternative. The typical response is to ignore, discount, or even actively suppress the new data.

Systematically irrational behavior by scientists has seemed odd enough that I have puzzled over it for years. The best explanation I have identified is that scientists are self-selected from among the population as those who feel a need to know, and to feel that they do know. To go from relying on one theory to considering two feels like going from knowing to only half-knowing. To discard a theory one has lived with feels like going from knowing something to knowing nothing. Both are, evidently, intolerable to most people who choose to become scientists.

The above does not suffice to explain the condition of astronomy.