When we read the primary scripture, the Book of Nature, scientifically, we assume that its development was continuous and consistent – that the Mind of its Creator does not contradict itself, but changes itself continuously (evolves), so that throughout any measurable span of spacetime, at least some of its legisigns continue to govern unfolding events. In science, when well-documented facts or observations appear to be mutually contradictory, we guess that there is something wrong with the theoretical framework(s) within which some of those facts have been hitherto understood.
Likewise, when a systematic philosopher such as Peirce appears to make an assertion incompatible with some previous assertion of his own, without giving any indication that the new assertion is a correction or improvement of the older one, our first guess should be that our interpretation of at least one of his statements is faulty. We could call this the principle of hermeneutic fallibilism. The next step is to look for a more comprehensive interpretation of the author’s work, whereby the statements in focus appear complementary rather than contradictory, or occupy different contextual niches in a consistent meaning space, or represent different stages in the development of a single consistent system. If we do come up with a more comprehensive interpretation, it may bear fruit in future readings of this writer’s work, revealing more of its depth, breadth and complexity – perhaps more than its author himself recognized. Or the hypothetical framework may prove incompatible with subsequent readings, and have to be discarded in its turn. If no such comprehensive interpretation seems to work, then the next hypothesis to try is that the author has changed his mind on the subject without giving notice of the change – or that his system is not so consistent as we thought.
Of course, all this deep reading requires sustained attention, which means not turning attention to other possible objects in the meantime.