What do you see here? The image at right is an example of a "Porphyrian tree," a representation of Porphyry's illustration of the scale of being described in Aristotle's categories, and widely cited as the earliest European tree diagram. I've seen versions of it in many histories but only today paused long enough over it to realize it's barely a tree at all. The account starts at the top, with "Substance," which divides into two, "corporeal" and "incorporeal." But then the one at left shifts to the center, "bodies" (= "corporeal substance") - in some versions this move is labeled "constitutes" - before splitting again. The next branch at left, "animate," again shifts to the center and splits again. Eventually you arrive at "homo" (= "mortal rational animal") which splits into individuals, "Socrates" and "Plato," before erupting in a tangle of roots.
What absurdity is this? If anything it's an object lesson in self-serving nested hierarchical binaries, more like a spider plant than a tree. Yet the people who feature this particular image in their histories don't remark on how utterly untreelike it is. For starters, trees grow from the roots below, not from the (literal!) crown, not to mention the way branches zigzag to become trunk... But then they don't notice that the figure standing next to this contorted bonsai is about to cut it down, either!
It's a bit of a tangent - all I need for my argument is the claim that early "tree diagrams" have only a notional connection with biological growth - but I'd like to know more about it. It's the frontispiece of a book published in Bologna in 1503 called Destructio sive eradicatio totius arboris Porphirii: magni philosophi ac sacrae theologiae doctoris eximii Augustini Anchonitani ordinis fratrum Heremitarum Sancti Augustini.
