20 July 2009

Logical Craft

Here are the fruits of my Victorian frailty. I took Kate's advice and made a sampler - not of a slogan, admittedly, but still something I can believe in. It made a very nice pair of afternoons - I sat out on my porch in the sunshine and our nice cool, 27C weather and had a pretend Victorian convalescence.

The sampler shows a formal way of writing a kind of logical operation known as modus tollens, followed by its proof by truth table. The embroidery is not quite finished; I'm going to sew in 'modus tollens' at the bottom but I made too many mistakes trying to write it out with the erasable fabric pen so I had to wash the fabric and let it dry before I could try again, but you get the main idea.

The little sideways horseshoe indicates a conditional statement and means 'if...then'. The tilda means 'not'. The three dots in the form of a triangle mean 'therefore'. So the top part reads '1. If P then Q; 2. not Q; therefore not P'. Then the truth table lines up all the possible truth values for the whole thing. In non-modal logic, statements can be only true or false but not both and not undertermined. Anyhow, it shows that a conditional is false when the antecedent (in this case P) is true and the consequent (in this case Q) is false.

So now I have my own embroidered version of a fundamental logical truth about the world. That makes me happy. I plan to make one for modus ponens next. Thanks, Kate, for the suggestion!


  1. That's inspired! And I'm flattered you acted upon my suggestion.
    I think I'm going to have to make one now.I don't imagine I'll come up with anything so clever or logical, but I have a few slogans in mind.
    Your stitching is lovely and neat although the photo is a little out of focus & I can only make out the french-knots clearly.
    I'm glad it helped ease things a little. I had a minor crisis on my hands last week and I found blanket-stitching my way through 2 evenings of angst and frustration to be very calming.
    May the sampler(s) have pride of place in your new abode!

  2. Kate - It was a very good suggestion! Formal logic is so much less messy than real life. That's not such a good way to put it - formal logic is real, too. Less messy than the social part of life, I suppose, is what I mean. So, it was nice to have something that I was in charge of and that made sense!

    Lucy - you're going to turn my head! Thank you.

  3. I really do love this craft and think you could market it to disillusioned hipsters somehow. I, for one, would buy it in a sleek frame.

  4. Thank you! I do actually sell some of my crafty things - my current hometown is craft central and a host to quite a few national craft and artisan fairs. This one will have to wait to be marketed, though; my visa for grad school expressly forbids me from being self-employed or conducting a business while in the UK. It's a pity because the bits of extra money it brings in are always welcome.