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Comment by barrkel | Hacker News Reader

I used DeMorgan's laws when refactoring Boolean expressions for clarity long before I learned that the laws had a name - they're entirely obvious and self-evident. I think the relative pointlessness of specifically classifying and naming them makes knowing of them by name obscure.

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These ideas are named to honor the person who did much of the grunt work to get them proven/accepted, but we continue to use the name as a convenience.

If you're working with educated people, it's a lot easier to say, "apply DeMorgan," than to say, "why don't you negate the clause, remembering to negate each of the internal clauses, and switching the and's to or's and vice versa."

There exist people who use the names to sound intellectual, and these people are annoying, but just because some people enjoy spouting (in the general public) "obscure" rules and names, that doesn't mean that using such names is without value.

In this case you could come up with a short name for it that doesn't refer to a person -- you could call it "logical duality", since, after all, it is both logical and a duality. But people know it as "DeMorgan", and in this context I think the most important thing is being understood. Those who don't know the law probably wouldn't recognize it if you called it "logical duality" either.

True, but this leads right back to barrkel's point that the laws themselves are easier to explain than the names. To wit, without words,

http://jasomill.at/DeMorgan.pdf

In the design of programming languages one can let oneself be guided primarily by considering "what the machine can do". Considering, however, that the programming language is the bridge between the user and the machine --- that it can, in fact, be regarded as his tool --- it seems just as important to take into consideration "what Man can think". (Dijkstra [1])

And this is why mathematics is useful to software engineering.

[1] http://www.cs.utexas.edu/~EWD/ewd01xx/EWD117.PDF

I had to puzzle it out the first few times. Then I found in a college course on hardware design that the rule was named after some guy, which I found gratifying.

I remember having quite a time doing a doubly-linked-list, the first time I had to think it through. Always wondered why that wasn't named after some bloke . . . :-)

Even obvious and self-evident theorems are still useful. The first theorem of graph theory is almost trivial. (If you add up all the degrees of the nodes in a graph, you have 2 times the number of edges.)

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