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قراءة كتاب The Game of Logic

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The Game of Logic

The Game of Logic

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دار النشر: Project Gutenberg
الصفحة رقم: 6

Propositions at the head of this Section.

We see, then, that the Universal Proposition


"All new Cakes are nice"


consists of TWO Propositions taken together, namely,

             "Some new Cakes are nice,"
        and "No new Cakes are not-nice."


In the same way

                      -----------
                     |     |     |
                     |  0  |  1  |
                     |     |     |
                      -----------

would mean "all x are y' ", that is,


"All new Cakes are not-nice."


Now what would you make of such a Proposition as "The Cake you have given me is nice"? Is it Particular or Universal?


"Particular, of course," you readily reply. "One single Cake is hardly worth calling 'some,' even."


No, my dear impulsive Reader, it is 'Universal'. Remember that, few as they are (and I grant you they couldn't well be fewer), they are (or rather 'it is') ALL that you have given me! Thus, if (leaving 'red' out of the question) I divide my Universe of Cakes into two classes--the Cakes you have given me (to which I assign the upper half of the cupboard), and those you HAVEN'T given me (which are to go below)--I find the lower half fairly full, and the upper one as nearly as possible empty. And then, when I am told to put an upright division into each half, keeping the NICE Cakes to the left, and the NOT-NICE ones to the right, I begin by carefully collecting ALL the Cakes you have given me (saying to myself, from time to time, "Generous creature! How shall I ever repay such kindness?"), and piling them up in the left-hand compartment. AND IT DOESN'T TAKE LONG TO DO IT!

Here is another Universal Proposition for you. "Barzillai Beckalegg is an honest man." That means "ALL the Barzillai Beckaleggs, that I am now considering, are honest men." (You think I invented that name, now don't you? But I didn't. It's on a carrier's cart, somewhere down in Cornwall.)

This kind of Universal Proposition (where the Subject is a single Thing) is called an 'INDIVIDUAL' Proposition.

Now let us take "NICE Cakes" as the Subject of Proposition: that is, let us fix our thoughts on the LEFT-HAND half of the cupboard, where all the Cakes have attribute y, that is, "nice."


                                            -----
  Suppose we find it marked like this:--   |     |
                                           |  1  |
  What would that tell us?                 |     |
                                            -----
                                           |     |
                                           |     |
                                           |     |
                                            -----

I hope that it is not necessary, after explaining the HORIZONTAL oblong so fully, to spend much time over the UPRIGHT one. I hope you will see, for yourself, that this means "some y are x", that is,


"Some nice Cakes are new."


"But," you will say, "we have had this case before. You put a red counter into No. 5, and you told us it meant 'some new Cakes are nice'; and NOW you tell us that it means 'some NICE Cakes are NEW'! Can it mean BOTH?"

The question is a very thoughtful one, and does you GREAT credit, dear Reader! It DOES mean both. If you choose to take

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