Tuesday, April 1, 2014

On knowledge and the meaning of "ex aequali" [non-China]

The advantages which Google, Yahoo and Wikipedia have brought to the curious mind are enormous. The amount of knowledge available to me at any instant is greater by a thousandfold than in the pre-internet era. I use Google and Wikipedia every day, and can't imagine going back to paper encyclopias and libraries.

Yet, as Socrates reminds us in the Meno, not all facts available to us are truely knowledge. Some, Socrates says, should rather be considered merely true opinions, since we believe them to be true without knowing why they are true.

But what the internet brings us is not even true opinions, but merely the capability to acquire such opinions. That is, it hasn't actually made us more knowledgeable, it's just given us the tools to more easily acquire opinions.

For this reason, I think that despite its benefits, the internet has taken some of the fun out of learning/not knowing things. Whereas in the past, I imagine (and perhaps vaguely recall) that you used to have to ask an expert if you didn't know something, in the present you can just search for it yourself. It seems inescapable that this trend will devalue knowledge as a social currency, i.e., make knowing knowledgeable people less of a boon than it was pre-Internet. When everything is a click away, why bother to memorize things?

As a sort of counter-response to this trend, I've chosen a username, Ex Aequali (which is also the URL of this blog), which is so obscure that it's immune to Google. It's virtually impossible to understand without some real knowledge, which a Google search alone won't bring you. But since nobody except for my fellow St. John's students gets the joke unless I explain it, I'll do so here.

"Ex aequali" is a term that comes up in Euclid, who we studied at St. John's. I would assume that it is medieval in origin, but it's certainly pre-Cartesian, and is used in non-algebraic math. It refers to this property of ratios:
If A:B as X:Y
and B:C as Y:Z
then ex aequali (through equals),
A:C as X:Z.

In modern terms, it's like multiplying the numerators or denominators on both sides of an equality. For example, if 1/4 = 3/12, and 4/8 = 12/24, then 1/8 = 3/24.

I hope posting this won't give away my secret. I do quite enjoy having a Google-proof username.


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