By David Weinberger
I know the earth is round. I know this because (I presume) when I was first introduced to the concept of the earth, it was by having a teacher hold a globe. Since then, everything I've been told and experienced has been consistent with the spherical nature first thrust before my young eyes. In fact, I saw a photograph of the entire earth in the late '60s, a sight never before seen by humans, as Stewart Brand noted movingly.
I know ants are insects. I knew this before it was explained to me in some early science class. Insects, we were told, have six legs, unlike those creepy arachnids. Until then, I thought spiders were insects. Nothing in my understanding of ants and spiders changed when I learned that one is an insect and the other isn't. My knowledge of this is certain in part because so little is at stake.
I know that 3 times 3 is 9. I know this because I memorized the times table. I also know how to check it if necessary. And, it has never failed me.
I know that 9 times 151 is 1,359. I know this because I learned a method for doing calculations. The method has never failed me, although I have sometimes failed at it.
I know that 1,542 times 9,458 is 14,584,236 because that's what my calculator says. I know a method for checking it, but as the terms get longer, the chances decrease that I will complete the method without making an error.
I know that the square root of 14,584,236 is 3818.9312641099. I know this because my calculator tells me. I don't have a method for deriving square roots. I do have a method of checking if my calculator is right, but see the previous paragraph.
I know that George Washington was the first president because someone told me and no one has contradicted it.
If all men are mortal and Socrates is a man, I know that Socrates is mortal. I know this for reasons I can't explain. If you can't see that it's a valid argument, I'm not going to be able to help you.
I know that the inside of a bag is slightly smaller than the outside. I know this not because I have ever measured it, but because the size of the outside has to be the size of the inside plus the thickness of the material. I know this because the inside of a bag is defined as the area enclosed by the bag.
I know I prefer Chinese food to Japanese. I know what I like to eat because I can think about the taste, but I actually don't have to do that; my knowledge is fully expressed in my saying, "I'd much rather do Chinese, if you don't mind."
I know I get lost easily. I know this because even if I'm driving somewhere I've been many times before, I take wrong turns. I know, also, about why I get lost: I can't "see" how road segments join. I can't picture where one road ends and another begins. I know this because I'm trying it right now--there's a street I've driven down hundreds of times in the past 20 years. I can picture the beginning and some shops along the way, but damned if I can see where it ends. I also know this because I am constantly surprised to find myself in some familiar spot.
I know my 13-year-old son's love of The Simpsons is unlikely to last forever. I know this because, even though he's pretty much memorized every episode, our tastes change over time.
I know my wife's love of the Alvin Ailey dance company probably won't change. We've gone every year for more than 20 years. Her delight seems intense. But, there's always the possibility that the dance company will deteriorate.
I know how to burn a CD. I know because I remember how I did it last time, and I remember that it worked.
I know how to play Mr. Tambourine Man on the guitar. I know how because I learned the chords when I was in high school, and I can still play them.
I know that I know the name of the male lead in the movie Twister, but I can't remember his name right now.
I know I'm worried about something, but I don't know what.
I know that getting a tattoo while you're drunk is a bad idea. Don't ask.
David Weinberger edits "The Journal of the Hyperlinked Organization", e-mail [email protected].