S. told me to prove the lemma "A iff B" (from his soon-to-be published book) for practice. "A only if B" was really easy, but the other direction was not clear. I tried it many different ways, and reduced it to several different statements C, D, E. I did not know whether C, D, or E was true. So I asked S. in our meeting today "is it the case that C?" and he said, "of course not!" This was befuddling, and I lost my way for awhile, so we talked about it. After both staring at it for a long time, I figured out that "A if B" was false by coming up with a counterexample.
Book debugging: a story of triumph!
This post's theme word: keming, "the result of improper kerning."
Wednesday, May 21, 2008
Saturday, May 17, 2008
Crooked
Yesterday marked three weeks since my surgery. I'm down to only one crutch, but yesterday this crooked crutching gave me a wicked full-body crick from being twisted asymmetrically. Two crutches, though preventing both hands from carrying items, are a symmetric mode of transport. There is a crick in my neck, in my shoulders, in my back, in my hip.
This post's theme word: strigil, "an instrument with a curved blade (used esp. to scrape sweat/dirt from the skin)."
This post's theme word: strigil, "an instrument with a curved blade (used esp. to scrape sweat/dirt from the skin)."
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