Euclid's first common notion is this: "Things which are equal to the same thing are equal to each other." That's a rule of mathematical reasoning. It's true because it works; has done and will always will do. In his book, Euclid says this is "self-evident." You see, there it is, even in that two-thousand year old book of mechanical law: it is a self-evident truth of things which are equal to the same thing, are equal to each other. We begin with equality. That's the origin, isn't it? That balance—that's fairness, that's justice.
Euclid's first common notion is this: "Things which are equal to the same thing are equal to each other." That's a rule of mathematical reasoning. It's true because it works; has done and will always will do. In his book, Euclid says this is "self-evident." You see, there it is, even in that two-thousand year old book of mechanical law: it is a self-evident truth of things which are equal to the same thing, are equal to each other. We begin with equality. That's the origin, isn't it? That balance—that's fairness, that's justice.
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