It is turning into what the philosopher called a ‘party from principle.’ That wasn’t a term of praise.
In a popular book of essays … Hume criticizes “parties from principle,” those organized around ideology. “Parties from principle, especially abstract speculative principle, are known only to modern times, and are, perhaps, the most extraordinary and unaccountable phaenomenon, that has yet appeared in human affairs.”
He contrasts them with parties “from interest,” which form around professional and geographical interests. The interests of farmers and sea merchants are different, which is reflected in their political allegiances. Parties of interest are alive and well on K Street in Washington.
Parties from principle produce fanatical behavior in a way that parties from interest don’t, Hume observed. Parties of interest compromise to get what they want, but ideological purists don’t. This was the root of religious wars and of present-day culture wars.
Hume explains that humans universally dislike ideas opposing their own, and when “superstition” (fear and ignorance) blends with “enthusiasm” (hope and ignorance), they do crazy things. Modern innovations—pamphleteering in Hume’s day, social media in ours—have made it easier to organize and motivate ideologues.
Viewed through Hume’s lens, Democrats’ intramural struggle with socialism is only the latest evidence that they are morphing from a party from interest into a party from principle.