Conservation law of child's blocks analogy

AI Thread Summary
The discussion centers on the conservation law illustrated through a child's blocks analogy, as presented in Feynman's Lectures on Physics. The analogy emphasizes that the total number of blocks (or energy) remains constant, regardless of their location. Participants question whether Feynman originated this analogy or if he adapted it from earlier sources. It is suggested that while Feynman may have popularized the concept, he likely drew inspiration from existing ideas. The conversation highlights the importance of tracing the origins of educational analogies in physics.
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Conservation law of child's blocks analogy
In Feynman's Lectures on Physics volume one there is an analogy to conservation of energy (though it would equally apply to other types of conservation). The idea is that if a child has n blocks we should always expect there to be n blocks. We may find the blocks somewhere we do not expect or find blocks from somewhere else, but we should find the n blocks each time. I have seen this analogy ripped of many times. What I want to know is did it start with Feynman or did he rip it off from somewhere else.
 
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He almost certainly ripped it from someplace else - but, afaict, he beat everyone into popular print.
 
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