§ 18. A Cataleptic Phantasy
Another idea with long legs compares the soul to a wax tablet, receiving impressions from outside through the senses. The Stoics are the classical advocates of this idea, though Plato invented it.
Zeno, founder of the Stoic school, supposedly explained phantasia (perception) as “an impression (typos) on the soul... involving depression and protrusion, just as does the impression made in wax by signet rings.” Animals and people alike receive such impressions; however, in people these impressions are endowed with logical content, being the impression that a given proposition is true. Such impressions are thoughts presented to the mind for assent or dissent. For a rational being, to have an impression is to think a thought, which means thinking a propositional content in a particular way. All the contents of the mind are thoughts. The whole difference between an emotion and any other state of mind is the way we entertain different propositions.148What Stoics call the phantasia kataleptike, the cataleptic phantasm, or cognitive impression, arises only from what is (apo huparchontos) and reproduces this being exactly as it is. This is stipulation: by definition, cataleptic phantasms cannot arise from what does not exist. Only oxen really look and move like oxen, and a perception cannot be a cognitive impression of an ox without really being an impression of an ox. It could appear to be an ox without really being an impression of an ox only to someone who had never seen oxen or who was impaired. The faculty of assent (synkatathesis) functions naturally and automatically to approve cognitive impressions, and knowledge grows through their accumulation. Only perceptual impressions are cognitive, and their truth is self-evident, or as Stoics say, enargeia, rendered by Cicero perspicuitas and evidentia.149
Cognitive impressions give rise to common notions. These are natural responses to cataleptic, cognitive impressions, forming without awareness. We simply find ourselves with certain concepts. They are not innate, not a Platonic reminiscence, but arise from an experience so ubiquitous that they might as well be innate. Stoicism’s decisive departure from empiricism comes with the idea that everything philosophically true of nature is a rational function of these common concepts, which the Stoic sage uses to calculate and prepare for the future. Stoics evince a touching faith in nature. We are meant by nature to live lives that are rational, virtuous, and happy. Since that requires knowledge, we are made for knowledge, and nature provides the required foundation in cognitive impressions. These cannot be false, and carry us to the knowledge we need for the wisdom a good life requires. It was this faith, a kind of rationalism, indeed, Aristotle’s kind, that the ancient Skeptics relentlessly attacked.