Each paradigm will be shown to satisfy more or less the criteria that it dictates for itself and to fall short of a few of those dictated by its opponent.

I never know whether to be more surprised at Darwin himself for making so much of natural selection, or at his opponents for making so little of it.

Science rests on reason and experiment, and can meet an opponent with calmness; [but] a creed is always sensitive.

…we are all inclined to ... direct our inquiry not by the matter itself, but by the views of our opponents; and, even when interrogating oneself, one pushes the inquiry only to the point at which one can no longer offer any opposition. Hence a good inquirer will be one who is ready in bringing forward the objections proper to the genus, and that he will be when he has gained an understanding of the differences.