Grice, "Entailment" (for Symposium for APA), The Grice Collection, BANC 90/135

by JLS
for the GC

--- FURTHER to the passage from Moore's 1919, "p ent q" -- a second reference to Barbara later on the same essay by Moore. He is considering something like transitivity:

"To say that it does follow from it
is to say from

[(p /\ q) /- r]

it follows that

[p ) q /- r]

which can be easily be seen
to be false by taking
for p and q the two premisses
in Barbara, and for r
the conclusion. The conjunction,
"All men are mortal and Socrates
is a man" does entail
"Socrates is mortal". But it
is obviously not the case
that there follows from this
what

[(p ) q) /- r]

asserts; namely, that it is NOT
the case that "All men are mortal" is
true and the proposition

"'Socrates is a mortal' FOLLOWS
from 'Socrates is a man'"

false. The proposition that
"Socrates is a mortal" follows
from "Socrates is a man" IS
false; and yet, "All men are
mortal" may quite well be true."

... He goes on using "materially implies" now:

Moore writes:

"The proposition "All men are mortal"
does entail that "Socrates is a man' materially
implies (to use Mr. Russell's expression for ))
"Socrates is mortal"; that is to say, it entails
that it is not the case both that "Socrates
is a man" is true, and "Socrates is mortal" false. But
it does not in the least follow from this
that "All men are mortal" materially implies
that "Socrates is a mortal" FOLLOWS from
"Socrates is a man"; on the contrary, it
may, as we have seen, well be the case that
"All men are mortal" is true and yet
the proposition that "Socrates is a man"
entails "Socrates is a mortal" false."

At this point one starts to wonder why Grice found it important to distinguish 'human' from 'person'! -- For Grice, _humans_ are mortal; persons ain't!