This will probably make you snooze, but I found it curious nonetheless:

The first of Boethius's four subdivisions was similitude, used of the case of the noun ‘animal’ said of both real human beings and pictured human beings. Medieval logicians seem to have been totally unaware of the fact that the Greek word used by Aristotle was genuinely polysemous, meaning both animal and image, and they explained the extended use of ‘animal’ in terms of a likeness between the two referents — a likeness which had nothing to do with the significate of the term ‘animal’, which picks out a certain kind of nature, but which was nonetheless more than metaphorical in that the external shape of the pictured object does correspond to that of the living object. ... [bold mine. -ed]

What it looks like happened is that in Aristotle's time a person and an image of that person may have been thought to be in some strong sense the same. As if things containing one's image were a part of one's body. By the time of the medieval logicians, the original sense - that is to say, not the definition itself but the way in which the definition is meant - was lost. Maybe unable to process the complications of this view, (recall superstitions about paintings and photographs) it was in some way discarded. The notion of similitude in analogy seems to have lost a lot of power inadvertently - perhaps not entirely in this fashion, but being ignorant of no more than their teachers and their interpretations of the often difficult Aristotle and the other Philosophers, it may have taken hold.

To wit, the analogic method became a process of identifying similarities between external shapes - and while the deeper sense of shared identity through form still persisted, it seems like for most Westerners who are not superstitious it became implicit and unconscious.

The superstitious aspect of this idea probably relates to a misunderstanding of soul, how it is the 'anima' of someone can be present in images of them, but yet this would pose no threat to them. It is in the same way that a projector of light can come to no real harm by attacks on its projection.

I made the assertion previously that it is possible to be logically consistent - and also insane. Now, I would not go so far as to say that one who is logically consistent (or tends towards logical consistency) is insane - but rather - let's just say, the door is open.

What I mean then is that something that is logically consistent is not necessarily sane, that is, in accordance with reality itself. (This is not that reality isn't logically inconsistent, but that we fall short of this consistency because of our limitations.)

The simplest form of this is a tautology: Something is because it is. Logically that's true; but it tells you nothing at all. What's insane in this case is not stating The Identity Property but rather assuming that that tells us something about that object other than that it exists (if it even does.) Imagine that the tautology is a tiny circle within the realm of all possible and existent things. While this loop is valid and consistent, it is far from complete both in terms of what is described (what color is it? how long has it existed? Who made it?) and in terms of describing all of reality. If we take the tautology to mean we know everything about something we are acting in an insane manner (whether purposefully, in jest or otherwise...)

So now that I've gotten that little bit straightened out (hopefully) I want to talk about the unifying principle. This will sound silly, but there is a movie called, "Bender's Big Score". It's the Futurama (a Matt Groening joint) movie. They introduce time travel into the series, but with a caveat. If paradoxes occur, instead of 'creating a new universe' multiverse theory, the universe 'naturally' resolves itself back to one. (Usually by killing the time traveling meddler.) This only goes so far, as (spoiler alert) at the end of the movie the robot Bender creates a situation that cannot be resolved by simply killing off the time travelers.