Richard Bellman on Multistage Decision Processes

& (verbiage overflow)Wed 01 October 2014RSS

I wish it weren’t so, but I find my mind has trouble learning a thing if its name doesn’t make sense. This weakness extends even to simple algebra, where I occasionally have trouble understanding the meaning of a variable that I can’t easily connect to a word — c for “speed of light”, for instance, bothered me until I remembered Latin celeritas [‘speed’]. In my new life as a programmer, one subject that took a long time to become clear was dynamic programming, because it seemed to me no more dynamic than any other sort of programming.

The name was coined by the mathematician Richard Bellman, who it turns out originally called it “multistage decision processes”. He renamed it “dynamic programming” purely for purposes of budgetary camouflage:

I felt I had to do something to shield [Secretary of Defense Charles E.] Wilson and the Air Force from the fact that I was really doing mathematics inside the RAND Corporation [in the 1950s]. What title, what name, could I choose? In the first place I was interested in planning, in decision making, in thinking. But planning, is not a good word for various reasons. I decided therefore to use the word ‘programming’. I wanted to get across the idea that this was dynamic, this was multistage, this was time-varying — I thought, let’s kill two birds with one stone. Let’s take a word that has an absolutely precise meaning, namely ‘dynamic’, in the classical physical sense. It also has a very interesting property as an adjective, and that is it’s impossible to use the word ‘dynamic’ in a pejorative sense. Try thinking of some combination that will possibly give it a pejorative meaning. It’s impossible. Thus, I thought “dynamic programming” was a good name. It was something not even a Congressman could object to. So I used it as an umbrella for my activities. (Richard Bellman, Eye of the Hurricane: An autobiography [Singapore: World Scientific Publishing Co Pte Ltd., 1984], p. 159.)

Wilson was originally an engineer but had extensive connections to industry. Bellman describes him as having “a pathological fear and hatred” of the word “research”. He and his President cut the U.S. defense budget substantially during the 1950s, hoping to put it on a rational basis more like that of industry. Whether or not you sympathize with that principle (or agree that it is rational), you can understand the suspicion someone with that background could have felt for “research”.


I see that many people have commented on Bellman’s story, quoting this very paragraph, in blog posts and elsewhere. How much repetition there is on the Internet! And how much of the writing on the Internet has to do with programming — it never ceases to amaze me. But it took me reading Bellman’s memoir for myself to find this quotation, so I will post it anyway, for myself. And I don’t think many of the people who are quoting Bellman have bothered to look up his book for themselves. It’s a curmudgeonly delight — a little unlettered and in need of editing, but an untempered pleasure to read even so. Today is my last day of borrowing privileges at the academic library near me, and Eye of the Hurricane was the very last book I returned.

It also doesn’t look to me as though many people quoting this passage have noticed how much more apt “multistage decision processes” is. I will try to keep it in mind.

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