ONT Re: De In Esse Predication
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DEIP. Note 3
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| [A Boolian Algebra With One Constant] (cont.)
|
| To express the proposition: "If S then P",
| first write:
|
| A
|
| for this proposition. But the proposition
| is that a certain conceivable state of things
| is absent from the universe of possibility.
| Hence instead of A we write:
|
| B B
|
| Then B expresses the possibility of S being true and
| P false. Since, therefore, SS denies S, it follows
| that (SS, P) expresses B. Hence we write:
|
| SS, P; SS, P.
|
| C.S. Peirce, CP 4.14, untitled paper circa 1880.
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