Doctrinaire

And he is not above feeling grave and well-contained satisfaction wherever the socialist doctrinaire has been contradicted by men attempting to practise coöperation in the midst of the competitive system, as in Belgium.

Source: wiktionary

Or, shall we play the doctrinaire, and hint that at thirty-four the tides of life are calmer and cognizant of many sources instead of but one—as at four-and-twenty?

Source: wiktionary

Mr. Chapman began to talk in a loud voice about the situation in the House of Commons. He guffawed at his adversaries. The word doctrinaire—word full of terror to the British mind—reappeared from time to time between his explosions.

Source: wiktionary

We have been long accustomed to consider growth as applied almost exclusively to size in its various aspects. But Nature, who has no doctrinaire ideas, may equally apply it to concentration.

Source: wiktionary