I have just found some quotes by Laurence Stern (24 November 1713 – 18 March 1768 an Irish novelist and an Anglican clergyman) which perfectly describe party politics and other polarising dogma.
"It is in the nature of an hypothesis, that once a man has conceived it, that it assimilates everything to itself, as proper nourishment; and, from the first moment of your begetting it, it generally grows stronger by everything you see, read, hear, or understand."
"It is a great pity but tis certain from every day's observation of man, that he may be set on fire like a candle, at either end, provided there is a sufficient wick standing out."
and "'Tis known by the name of perseverance in a good cause, and of obstinacy in a bad one" or perhaps, of perseverance if you concur, of obstinacy if you don't.