My argument against allegiance with a political party is this: Prejudicial bias is a necessary condition of party allegiance. One should avoid bias; therefore, one should avoid party allegiance.

The first premise simply means that whenever you have loyalty and devotion to a political party, you’ll necessarily also be prejudicially biased. Besides seeming obviously true from experience, the motivation for this premise is that numerous studies in psychology demonstrate the negative effects that in-group bias has on judgment, even when the groups are randomly assigned and made up of people with whom the participants have never met. Studies consistently show that in-group members develop irrational prejudices of the out-group members (see Section V of “The Psychology of Judgment and Decision Making,” by Scott Plous). The first premise asserts that this phenomenon is also present in political groupings.

(As an aside, if you believe that Democrats do nothing but smoke pot and collect welfare checks, or that Republicans hate women and minorities and want to do away with civil rights, you are probably suffering from in-group bias.)

With respect to the premise that one should avoid bias, I have three motivating reasons, each pertaining to the negative effects of in-group/out-group bias. First, the prejudice generated from this bias promotes unfair stereotyping of the other group. Second, bias has the tendency to make one minimize or explain away the faults of their own group and exaggerate the faults of the other group, attributing their faults to their evil nature. And finally, this creates an epistemic barrier to arguments from the other side: We inadvertently reject sound arguments on the prior assumption that the other side is always wrong or has ill motives. This suggests that our ability to detect truth in arguments depends in part on who is making the argument and the amount of bias we have for or against that person. I think that these negative effects intuitively suggest that we should avoid being biased.

Finally, the conclusion logically follows that one should avoid party allegiance. A good alternative is to be like an impartial spectator: One whose political affiliation is not integral to their personal identity, and who has no stake in promoting a superior view of one party over another. I suggest that we strive for the ideal of cool, rational discourse in which we are equally critical of all arguments, avoiding demagoguery like the plague, and always giving a careful evaluation of evidence. I can imagine someone objecting to my argument on the possibility that one could have a strong political affiliation and yet be perfectly unbiased. To this I simply reply: I’ll believe it when I see it.