Grice's slide -- Marmaduke Bloggs 'slide'

Grice notes that slides are "dangerous instruments of proof", but that they are okay if they are used to 'back up a theoretical proposal'. The slide he proposes concerning Marmaduke Bloggs involves 7 steps:

STEP 1:

To say "Marmaduke Bloggs is at this party" would be to say something which is NOT true.

STEP 2:

To say "It is NOT true that Marmaduke Bloggs is at this party" would be to say something which is TRUE.

STEP 3:

To say "Marmaduke Bloggs is not at this party" would be to say something which is TRUE.

---- (cfr. "The king of France is not bald")

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STEP 4:

"Marmaduke Bloggs is not at this party." (in Grice's view)

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STEP 5:

Also in Grice's view:

"Marmaduke Bloggs can be TRULY said NOT to be at this party.

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STEP 6:

Also in Grice's view and idiolect, or idiosyncratic system:

"Someone (viz. Marmaduke Bloggs) can be TRULY said NOT to be at this party."


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Finally:

Step 7:

In Grice's view and idiolect/idiosyncrasy (shared, as it happens, by me):

"Someone is not at this party (viz. Marmaduke Bloggs)" -- or at least something?

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