Cf: Peirce’s 1870 “Logic of Relatives” • Selection 1
https://inquiryintoinquiry.com/2014/01/27/peirces-1870-logic-of-relatives-s…
All,
We pick up the text at §3. Application of the Algebraic Signs to Logic.
Peirce’s 1870 “Logic of Relatives” • Selection 1
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https://oeis.org/wiki/Peirce%27s_1870_Logic_Of_Relatives_%E2%80%A2_Part_1#S…
<QUOTE CSP>
Use of the Letters
==================
The letters of the alphabet will denote logical signs.
Now logical terms are of three grand classes.
The first embraces those whose logical form involves only the conception
of quality, and which therefore represent a thing simply as “a ──”. These
discriminate objects in the most rudimentary way, which does not involve any
consciousness of discrimination. They regard an object as it is in itself as
such (quale); for example, as horse, tree, or man. These are absolute terms.
The second class embraces terms whose logical form involves the conception
of relation, and which require the addition of another term to complete the
denotation. These discriminate objects with a distinct consciousness of
discrimination. They regard an object as over against another, that is
as relative; as father of, lover of, or servant of. These are simple
relative terms.
The third class embraces terms whose logical form involves the conception
of bringing things into relation, and which require the addition of more
than one term to complete the denotation. They discriminate not only with
consciousness of discrimination, but with consciousness of its origin.
They regard an object as medium or third between two others, that is as
conjugative; as giver of ── to ──, or buyer of ── for ── from ──.
These may be termed conjugative terms.
The conjugative term involves the conception of third, the relative that of
second or other, the absolute term simply considers an object. No fourth class
of terms exists involving the conception of fourth, because when that of third is
introduced, since it involves the conception of bringing objects into relation, all
higher numbers are given at once, inasmuch as the conception of bringing objects into
relation is independent of the number of members of the relationship. Whether this
reason for the fact that there is no fourth class of terms fundamentally different
from the third is satisfactory of not, the fact itself is made perfectly evident
by the study of the logic of relatives.
(Peirce, CP 3.63)
</QUOTE?
One thing that strikes me about the above passage is a pattern
of argument I can recognize as invoking a closure principle.
This is a figure of reasoning Peirce uses in three other places:
his discussion of continuous predicates, his definition of a
sign relation, and his formulation of the pragmatic maxim itself.
One might also call attention to the following two statements:
<QUOTE CSP>
Now logical terms are of three grand classes.
No fourth class of terms exists involving the conception of fourth, because
when that of third is introduced, since it involves the conception of bringing
objects into relation, all higher numbers are given at once, inasmuch as the
conception of bringing objects into relation is independent of the number of
members of the relationship.
</QUOTE>
Regards,
Jon