WHAT VEGETABLES ARE SAYING ABOUT THEMSELVES
Schopenhauer argues that plants are manifestations of will—they just grow. In this sense, plants are just like algorithms, since algorithms don't know anything about number, they just execute computations. Thus algorithmic models of plants work just like plants, hence the success of the beautiful book The Algorithmic Beauty of Plants. A flower is a plot of an algorithm.
In this sense, a trope is an algorithm—a twist of language that emerges as meaning, by simply following a recipe (such as “jam two nouns together with the verb to be between them”). A trope is a flower of rhetoric, which is imagined as vegetative (anthos, hence anthology). Thus Milton's Satan curls around like a snake trying to turn into a vine.
That's what is disturbing about rhetoric and algorithms and plants and Satan—they exhibit a zero degree of intelligence, or not…we can't know in advance. Plants disturb us with what Lacan says “constitutes pretense”: “in the end, you don't know whether it's pretense or not.” They might be lying, which in a sense means that they are lying.
Just as an algorithm could pass a Turing Test—I could discern thinking and personhood in this “blind” execution—so plants are posing, and passing Turing Tests all the time. In looking at a flower, you are doing the flower's job. Bees complete the Test all the time, by following the flower's nectar lines. Or, as Schopenhauer puts it, plants want to be known, because they can't quite know themselves.
Indeed, a plant in this sense is the zero degree of personhood—as Nietzsche said, people are halfway between plants and ghosts. This zero degree is a weird, twisted loop that says something like “This is not just a plant.” Consider the zero degree of the Cartesian cogito: the paranoia that I might simply be a puppet of some demonic external force. Isn't this just the creeping sensation that I might just be a vegetable?
In this sense, T.S. Eliot's line about flowers is perfect, from the plant's own point of view: “The roses / Had the look of flowers that are looked at.”