Esprit de corps is liked by authorities, because it enables them to utilize bad motives for what are considered to be good actions. If efforts are to be made, they are easily stimulated by promoting the desire to surpass some other group. The difficulty is that no motive is provided for efforts which are not competitive.
Source: On Education, especially in early childhood, 1926, Pt. 2： Education of character, chap. 5: Play and fancy
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