The above Latin phrase which I've adopted as a motto encapsulates as well as any phrase could the fundamental shift in my thinking that has occurred over the past couple of years. It was coined by Vico in a passage of the Scienza Nuova where he discusses the ubiquity of bodily metaphors in speech ("eye of a needle", "heart of the city", "head of foam", "teeth of a saw", "mouth of a cave", etc.):
"It is noteworthy that in all languages the greater part of the expressions relating to inanimate things are formed by the metaphor from the human body and its parts and from the human senses and passions. [. . .] All of which is a consequence of our axiom that man in his ignorance makes himself the rule of the universe, for in the examples cited he has made of himself the entire world. So that, as rational metaphysics teaches that man becomes all things by understanding them (homo intelligendo fit omnia), this imaginative metaphysics shows that man becomes all things by not understanding them (homo non intelligendo fit omnia); and perhaps the latter proposition is truer than the former, for when man understands he extends his mind and takes in the things, but when he does not understand he makes the things out of himself and becomes them by transforming himself into them." (§405)
The only sticky point about the translation of the Latin is in just how we should interpret intelligendo. Fortunately Vico provides this in an earlier passage:
"Now the mind uses the intellect when, from something it senses, it gathers something which does not fall under the senses; and this is the proper meaning of the Latin verb intelligere." (§363)
Indeed, intelligere was used to mean "to understand, to comprehend, to discern", but Vico himself would encourage us to look a little deeper at its roots: inter- of course means "between"; legere is a little trickier. It was often used to mean "to read" but also "to select/choose", which seems an odd combination until you know its earlier meaning, which was "to gather/collect" (from the PIE root leg- of that meaning), and then think about English idioms like "I gather his meaning" and "I picked up on the metaphor".
So intelligere could be rendered "to choose between" or "to read between" or "to gather between", but all of these refer to essentially the same sort of activity: Plucking out the best from a set of possibilities. Whether you're collecting physical objects, interpreting statements or trying to guess at more abstract patterns, you're using your intelligence to
select the best solution according to some criteria (though these need not be explicit). To put it in computational terms, you're incorporating current sensory stimulation into your existing data set and curve-fitting it-which is pretty much what we mean by comprehension or understanding: having an internal model that matches the data well.
But all models are approximations to the world, which is why homo non intelligendo-as Vico would put it, none but God truly understands things completely. The amount of information you receive from your environment is nowhere remotely near enough to form a complete representation of it, nor is the amount of storage and processing power in your noggin anywhere near enough to specify an exhaustive model of anything but very simple systems, so your brain economizes everywhere it can to squeeze the most representational power out of what little it has to work with. Hence when we hit something we've never seen before, our best guess about how to model it comes from whatever pre-existing schema it strikes us as most similar to. Thus, homo fit omnia. As Piaget once put it: "Intelligence organizes the world by organizing itself."
For Vico, a mind can only understand what it has made, and thus "in God, knowledge and creation are one and the same thing" (§349). Here Vico can be seen as an early
constructivist, and we can agree with him on this point: What we have access to is mental representations, and we
mix this up with having access to external objects at our peril. Contrariwise, the whole motivation of his "new science" was his belief that in order to comprehend a thing (humanity, in this case) one has to understand the process that created it. Vico's philological savvy informs him here: If we say that we want to know the nature of something, this means knowing its origins, since natura literally means "birth". (Which, as an aside, is the Latin cognate for the Greek physis; see how much you can cash out from that.) Whether or not we follow him on this point in general, it certainly seems to hold true when dealing with complex, evolved systems (whether biological or social).
In this spirit, Vico was seeking a science of human institutions, using the tools of philology to uncover changes in human thinking; taking it as an axiom that "the order of ideas must follow the order of institutions" (§238), Vico declares:
"In search of these natures of human institutions our Science proceeds by a severe analysis of human thoughts about the human necessities or utilities of social life, which are the two perennial springs of the natural law of nations. In its second principal aspect, our Science is therefore a history of human ideas, on which it seems the metaphysics of the human mind must proceed." (§347)
"And they [philosophers and philologians] should have begun with metaphysics, which seeks its proofs not in the external world but within the modifications of the mind of him who meditates it. For since this world of nations has certainly been made by men, it is within these modifications that its principles should have been sought." (§374)
He failed at his ostensible task, of course, but the insights encountered along the way were well worth the journey. Those of us seeking an understanding of the human mind would do well to heed the lesson; theories about the mind formed in ignorance of its natura are unlikely to lead to truth. Those of us seeking to understand ourselves can only be aided by understanding our evolution.