American Scientist

To the Editors:

Congratulations to Henry Petroski for his Engineering column “ An Anthropomorphic Model ” in the March–April issue. I hope many high school students see that article and that their science teachers will carry out enactments such as those shown in Petroski’s article of the Forth Bridge. Anthropomorphizing a problem in mechanics can be a great help to fully understanding a concept, especially in design. My late friend and colleague Frank McClintock from Massachusetts Institute of Technology advised students when they encountered trouble with solving a problem in mechanics, “Anthropomorphize it.” One student, in an attempt to calculate the load required to hold a billboard fixed to a single vertical shaft in a high wind, came up with a serious underestimate. McClintock said to him, “Do you really believe you could hold that sign in place yourself?” The student got it and returned later with a correct answer. Anthropomorphizing problems is very helpful in training students, because it gives them a way to criticize their own results. As Benjamin Baker demonstrated in his design of the Forth Bridge, it can be equally helpful when professionals use this exercise.

Charles A. Berg
Mechanical Engineering, Emeritus
Northeastern University
Boston, MA