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===Commentary Note 8.1===
===Commentary Note 8.1===
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To my way of thinking, CP 3.73 is one of the most remarkable passages in the history of logic. In this first pass over its deeper contents I won't be able to accord it much more than a superficial dusting off.
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To my way of thinking, CP 3.73 is one of the most remarkable passages in the history of logic. In this first pass over its deeper contents I won't be able to accord it much more than a superficial dusting off.
Let us imagine a concrete example that will serve in developing the uses of Peirce's notation. Entertain a discourse whose universe <math>X\!</math> will remind us a little of the cast of characters in Shakespeare's ''Othello''.
Let us imagine a concrete example that will serve in developing the uses of Peirce's notation. Entertain a discourse whose universe <math>X\!</math> will remind us a little of the cast of characters in Shakespeare's ''Othello''.
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The universe <math>X\!</math> is "that class of individuals ''about'' which alone the whole discourse is understood to run" but its marking out for special recognition as a universe of discourse in no way rules out the possibility that "discourse may run upon something which is not a subjective part of the universe; for instance, upon the qualities or collections of the individuals it contains" (CP 3.65).
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The universe <math>X\!</math> is "that class of individuals ''about'' which alone the whole discourse is understood to run" but its marking out for special recognition as a universe of discourse in no way rules out the possibility that "discourse may run upon something which is not a subjective part of the universe; for instance, upon the qualities or collections of the individuals it contains" (CP 3.65).
In order to provide ourselves with the convenience of abbreviated terms, while preserving Peirce's conventions about capitalization, we may use the alternate names <math>^{\backprime\backprime}\mathrm{u}^{\prime\prime}</math> for the universe <math>X\!</math> and <math>^{\backprime\backprime}\mathrm{Jeste}^{\prime\prime}</math> for the character <math>\mathrm{Clown}.\!</math> This permits the above description of the universe of discourse to be rewritten in the following fashion:
In order to provide ourselves with the convenience of abbreviated terms, while preserving Peirce's conventions about capitalization, we may use the alternate names <math>^{\backprime\backprime}\mathrm{u}^{\prime\prime}</math> for the universe <math>X\!</math> and <math>^{\backprime\backprime}\mathrm{Jeste}^{\prime\prime}</math> for the character <math>\mathrm{Clown}.\!</math> This permits the above description of the universe of discourse to be rewritten in the following fashion:
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<math>\begin{array}{*{15}{c}}
<math>\begin{array}{*{15}{c}}
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1
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\mathbf{1}
& = & \mathrm{B}
& = & \mathrm{B}
& +\!\!, & \mathrm{C}
& +\!\!, & \mathrm{C}