If the principle of charity is not applied to the ideas of another, we seek falsity rather than the truths they hold. And when we presume this way (that another is prone to the false), we are in real danger of dehumanizing everyone who believes differently than we because the predicate is that they are unlike us; they are “other” rather than “another”. They must not think as we and cannot distinguish between truth and falsity, or must favor the false. From there, all damage is done.
Paraphrase of: Karen Armstrong, Epilogue, The Bible: A Biography, on Donald Davidson and our current cultural climate, religious or otherwise.