Can you explain to an ideologue the difference in their thought process and that of a pragmatist?

In a discussion or debate, it’s not uncommon for each debater to think the other is an ideologue, frozen immovably into a positing by ideology rather than evidence, and only willing to accept “facts” that agree with and support the conclusion their ideology requires. Sometimes that’s the actual case. We’ve probably all seen two ideologues from opposite poles duke it out in words here.

However, it’s often true that one is not an ideologue. Even an empiricist who weighs all evidence for its value and lets the facts guide them to the best solution will appear to the disagreeing ideologue to be applying fudge factors and rejecting the “important” evidence for that which, unfortunately, conflicts with the outcome the ideologue desires. Is it possible to get past that, or is debate with ideologues just a useless waste of time?