Seeing v. BelievingPosted: March 2, 2012
In his Discourse on Method, Descartes compares all sensory perception to the sight of somebody with jaundice. The jaundiced man sees everything with a yellow tint and it would be a mistake for him to believe that everything in the world really is yellow simply because he sees it that way. To Descartes, everybody is in this situation: our perceptions and impressions are not perfect, so it is a mistake to assume that everything actually is the way we see it.
Descartes uses the stars as an example of how flawed our perception is; the moon looks much larger than the stars, but we “know” that the stars are tremendously larger than the moon. However, it seems outrageously impractical to go about doubting all of our perceptions. When I buy a bottle of beer, I know that it will fit in my refrigerator by looking at it. I never stop and say, “this bottle looks to me as if it is smaller than my refrigerator, but I know that my senses are not to be trusted, so I had better measure it.” There are, of course, times when “eye-balling” is not adequately certain and measuring really is necessary, but for most day-to-day activities these cases are the exception rather than the rule.
Occasionally we do misjudge the height of a stair or mistake a glass wall for an open door, but how does that small inconvenience compare to the paralysis that would come from completely doubting our senses? Seeing is believing, and for the most part, that is a good thing.
Beer of the Week: Henninger Lager – This German import smells almost like a classic pilsner; the aromatic hops predominate. The flavor, however, is more malty, almost bready, with a faint hint of citrus. The finish has a nice little bit of spice from the hops. Unfortunately, the mouthfeel is a bit “wet” and “sticky”. Overall, it is not too bad a beer.
Reading of the week: The Ghosts by Lord Dunsany – This very, very short story is pretty interesting. (Also it contains a reference to Euclid, and that is pretty sweet.) In it, the narrator relates an “experiment” he undertook to prove to his brother that one can see ghosts without believing in ghosts.
Question of the week: Was the experiment a success?