Tyler has some dismissive observations about the practice of dismissal:

One of the most common fallacies in the economics blogosphere — and elsewhere — is what I call “devalue and dismiss.”  That is, a writer will come up with some critique of another argument, let us call that argument X, and then dismiss that argument altogether.  Afterwards, the thought processes of the dismisser run unencumbered by any consideration of X, which after all is what dismissal means.  Sometimes “X” will be a person or a source rather than an argument, of course.

The “devalue” part of this chain may well be justified.  But it should lead to “devalue and downgrade,” rather than “devalue and dismiss.”

I’m tempted to object, “Thank goodness for dismissal, because most ideas and thinkers are a waste of time.”  But on reflection, Tyler’s overly optimistic.  Dismissing ideas often requires rare intellectual discipline.  Psychologists have documented our assent bias: Human beings tend to believe whatever we hear unless we make an affirmative effort to question it.  As a result, our heads naturally accumulate intellectual junk.  The obvious remedy is to try harder to “take out the trash” – or refuse to accept marginal ideas in the first place.

The deeper problem: People are bad at Transfer of Learning, so dismissing an idea in general terms does not prevent it from swaying your judgment in individual cases.  Few adults deny the power of supply and demand in general terms.  But when they think about labor markets, many remain crude Marxists: “Working conditions are terrible!  Let’s pass a law!”  The problem continues throughout the knowledge pyramid: A person can recognize that supply and demand govern the labor market, but remain a crude Marxist when he talks about labor in the 19th-century or Third World.

The upshot is that full-fledged dismissal requires puritanical intellectual discipline.  This discipline is not always a virtue.  If your principles are poisonous, inconsistency dilutes the damage.  But right or wrong, whole-hearted (“whole-minded”?) dismissal is, contra Tyler, in short supply.