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Continue to ChatI can never satisfy myself until I can make a mechanical model of a thing. If I can make a mechanical model, I can understand it. As long as I cannot make a mechanical model all the way through I cannot understand. - Lord Kelvin from https://whatsmyquote.com/quote/i-can-never-satisfy-myself-until-i-can-make-a-mechanical-model-of-a-thing-if-i-can-make-a-mechanical-model-i