Nominalism, Idealism, and Realism
A while ago, there was some discussion on SUO list about
nominalism, idealism, and realism.
Following are definitions of those terms, which Peirce wrote
for the _Century Dictionary_. The excerpt below is taken
from the introduction to volume 1 of _The Essential Peirce_.
It also includes some discussion about Peirce's philosophical
development, as he progressed through those stages of thought.
At the end of the excerpt is the URL for the complete intro,
which was written by Nathan Houser.
John Sowa
__________________________________________________________
Probably the most significant development in Peirce's intellectual life
was the evolution of his thought from its quasi-nominalist and idealist
beginnings to its broadly and strongly realist conclusion. Because there
are so many variants of these doctrines, a few selections from Peirce's
Century Dictionary definitions will help reveal his conceptions of these
terms:
Nominalism: 1. The doctrine that nothing is general but names;
more specifically, the doctrine that common nouns, as man, horse,
represent in their generality nothing in the real things, but
are mere conveniences for speaking of many things at once, or
at most necessities of human thought; individualism.
Idealism: 1. The metaphysical doctrine that the real is of the
nature of thought; the doctrine that all reality is in its nature
psychical.
Realist: 1. A logician who holds that the essences of natural
classes have some mode of being in the real things; in this sense
distinguished as a scholastic realist; opposed to nominalist.
2. A philosopher who believes in the real existence of the external
world as independent of all thought about it, or, at least, of the
thought of any individual or any number of individuals.
Peirce also defined "ideal-realism" as "a metaphysical doctrine which
combines the principles of idealism and realism." As a variant of this
term, he defined the ideal-realism of his father [the mathematician
Benjamin Peirce] as "the opinion that nature and the mind have such a
community as to impart to our guesses a tendency toward the truth, while
at the same time they require the confirmation of empirical science."
The life-long tension between nominalism and realism in Peirce's own
intellectual life is testament to the general importance he attached to
it; in fact, if any single question can be said to have been viewed by
Peirce as the most important philosophical question of his time, it is
that of deciding between the two doctrines. Peirce concurred in this
with his old schoolmate Francis Ellingwood Abbot, who in 1885 wrote that
"so far was the old battle of Nominalism and Realism from being fought
out by the end of the fifteenth century that it is to-day the deep,
underlying problem of problems, on the right solution of which depends
the life of philosophy itself in the ages to come." (15) For Peirce, as
for Abott, the significance of the outcome of this "battle" was not
limited to technical philosophy:
though the question of realism and nominalism has its roots in the
technicalities of logic, its branches reach about our life. The
question whether the genus homo has any existence except as
individuals, is the question whether there is anything of any
more dignity, worth, and importance than individual happiness,
individual aspirations, and individual life. Whether men really
have anything in common, so that the community is to be considered
as an end in itself, and if so, what the relative value of the two
factors is, is the most fundamental practical question in regard
to every institution the constitution of which we have it in our
power to influence.
According to Fisch, Peirce's progress toward realism began early and was
gradual, but there were key steps that divide it into stages. (16)
Peirce took his first deliberate step in 1868 when, in the second paper
of his cognition series (item 3), he "declares unobtrusively for
realism." Although this step marks only a small shift in Peirce's
thought — the introduction of "the long run" into his theory of reality
— it is an important one, for it brings to an end his period of avowed
nominalism.
Peirce's second deliberate step was taken in 1871, when in his Berkeley
review he again declared for "the realism of Scotus" and recognized that
realism is temporally oriented toward the future while nominalism is
oriented toward the past. Fisch points out that this second declaration
came, when after a period of intensive study of the schoolmen, Peirce
had become well acquainted with the writings of Duns Scotus.
Peirce took his third step in mid-1872 when, in the Cambridge
Metaphysical Club, he first presented his pragmatism in which the
meaning of conceptions is referred to future experience: "So we say that
the inkstand upon the table is heavy. And what do we mean by that? We
only mean that if its support be removed it will fall to the ground....
So that ... knowledge of the thing which exists all the time, exists
only by virtue of the fact that when a certain occasion arises a certain
idea will come into the mind" (W3:30-31). A few months later, Peirce
wrote that "no cognition ... has an intellectual significance for what
it is in itself, but only for what it is in its effects upon other
thoughts. And the existence of a cognition is not something actual, but
consists in the fact that under certain circumstances some other
cognition will arise" (W3:77). But the best known statement of the
doctrine came in 1878, in the second of his "Illustrations of the Logic
of Science," in the now famous version of his pragmatic maxim: "consider
what effects, which might conceivably have practical bearings, we
conceive the object of our conception to have. Then, our conception of
these effects is the whole of our conception of the object." Fisch stops
enumerating the steps toward realism in 1872, and divides the rest of
Peirce's development into two periods, the pre-Monist period (1872-1890)
and the Monist period (1891-1914). He summarizes the key factors of the
former period as follows:
The chief developments in the pre-Monist period whose effects on
Peirce's realism will appear in the Monist period are his pragmatism;
his work on the logic of relations and on truth-tables, indices, and
quantification; the resulting reformulation of his categories; his work
and that of Cantor and Dedekind on transfinite numbers; the appearance
in 1885 of provocative books by Royce and Abbot; and, at the end of the
period, a fresh review of the history of philosophy for purposes of
defining philosophical terms for the Century Dictionary.
In the pre-Monist period, a step that had special importance for
Peirce's philosophical development was his recognition, with the help of
his Johns Hopkins student O. H. Mitchell, of the need for indices in his
algebra of logic. Peirce recognized the need for indices in notations
adequate for the full representation of reasoning because he had come to
understand the importance of pinning down thought to actual situations.
"The actual world," he said, "cannot be distinguished from a world of
imagination by any description. Hence the need of pronouns and indices"
(item 16). Fisch points out that Peirce's incorporation of indices into
his system of logic called for a reformulation both of his theory of
signs and of his general theory of categories. It was then that Peirce
reintroduced the familiar icon-index-symbol trichotomy and his
reformulated categories denoting three kinds of characters (singular,
dual, and plural), which he associated with three kinds of fact: "fact
about an object, fact about two objects (relation), fact about several
objects (synthetic fact)" (W5:244).
At the end of the pre-Monist period, Peirce took a major step toward a
more robust realism, a step related to his recognition of the need for
indices. This was his acceptance, in about 1890, of Scotus's
haecceities—the reality of actuality or of secondness. Peirce could no
longer ignore the "Outward Clash," as Hegel had much to the detriment of
his system of philosophy. With the acceptance of the reality of seconds,
Peirce acknowledged the mode of being that distinguishes the individual
from the general, and isolated his categories of fact: qualia,
relations, and signs.
The Monist period began with the series of five papers that concludes
the present volume. It is the first of four series of papers that Peirce
contributed to the Monist which, after its founding in 1890, became his
chief medium of publication. In each of these series, and in many of his
other writings of the period, he continued to weed out the remaining
nominalistic and many of the idealistic elements of his philosophy.
Peirce took his most decisive step toward realism in 1897. Fisch has
nicely illustrated this last great step by contrasting two passages, one
from a January 1897 review of the third volume of Schr&3246der's Algebra
und Logik der Relative, and the other from an 18 March 1897 letter to
William James. In January, Peirce wrote: "I formerly [as late as October
1896] defined the possible as that which in a given state of information
(real or feigned) we do not know not to be true. But this definition
today seems to me only a twisted phrase which, by means of two
negatives, conceals an anacoluthon" (CP 3.527). Two months later he
wrote to James: "The possible is a positive universe, and the two
negations happen to fit it, but that is all" (CP 8.308). Peirce thus
added the possible as a third mode of being—and, in so doing, gave up
his long-held, Mill-inspired frequency theory of probability—and his
scheme of categories was fundamentally complete. To his categories in
their form of thirdness (feeling, or signs of firstness; sense of action
and reaction, or signs of secondness; and sense of learning or
mediation, or signs of thirdness) and in their form of secondness
(qualia, or facts of firstness; relations, or facts of secondness; and
signs, or facts of thirdness), Peirce now added what might be called his
ontological categories, his categories in their form of firstness:
firstness, or the being of positive qualitative possibility; secondness,
or the being of actual fact; and thirdness, or the being of law that
will govern facts in the future (CP 1.23).
Peirce was then, in 1897, what Fisch calls a "three-category realist."
He had very early accepted the reality of thirds, the universe of
thought or signs. This universe was the only reality Peirce the idealist
had admitted until about 1890 when he accepted the reality of seconds,
the universe of facts (influenced by Scotus). Finally, in 1897 he
broadened his evolving realism to accept the reality of firsts, the
universe of possibility (influenced by Aristotle). Recognizing the
significance of these steps for the growth of his thought, Peirce now
characterized himself as "an Aristotelian of the scholastic wing,
approaching Scotism, but going much further in the direction of
scholastic realism" (CP 5.77n1).
One further step from the Monist period should be mentioned, for it
brings together two fundamental strands of Peirce's thought: his
pragmatism and his semiotic. In his third Monist series, beginning in
1905, Peirce sought to prove his doctrine of pragmatism (pragmaticism),
and in the course of working out his proof, he wove his two great
theories into a unified doctrine. He concluded that his semiotic
pragmatism entails realism, so that a proof of pragmatism is, at the
same time, a proof of realism, and that the pragmatist is "obliged to
subscribe to the doctrine of a real Modality, including real Necessity
and real Possibility" (CP 5.457).
Although Peirce was aware that at least some of the steps described
above were important milestones in his development, he did not regard
them as ushering in new systems of thought. According to Murphey, Peirce
regarded each phase of his thought as merely a revision of "a single
over-all architectonic system" and always preserved as much as he could
from each earlier phase. His philosophy might be likened to "a house
which is being continually rebuilt from within." (18)
Some scholars have not accepted the one-system account of Peirce's
philosophy. Thomas Goudge, in particular, has argued that "Peirce's
ideas fall naturally into two broad groups whose opposite character is a
reflection of a deep conflict in his thinking" and that this opposition
is the result of his conflicting commitment to both naturalism and
transcendentalism. (19) By "naturalism" Goudge has in mind scientific
philosophy more or less in the positivist sense, a philosophy that puts
logical analysis on a pedestal and eschews speculation and
system-building. Transcendentalism, on the other hand, discounts logical
analysis in favor of metaphysical construction, embracing both
speculation and architectonic. Peirce the naturalist tended to
nominalism, while Peirce the transcendentalist tended to realism. It was
Peirce the naturalist who was the pragmatist, while Peirce the
transcendentalist tended to intuitionism. Goudge finds that Peirce's
naturalism was the stronger tendency, which guided him in his researches
in formal logic, semiotic, scientific method, phenomenology, and
critical metaphysics, while the weaker transcendentalism "is most
apparent in his views on cosmology, ethics, and theology." (20)
Goudge has indeed uncovered what may appear to be two Peirces, but the
finding of most recent scholarship is that the tension is not as great
as he thought. Peirce's philosophy is broad and subtle and appears to be
able to accommodate results that would be incompatible in narrower
systems of thought. It is not possible here to argue for the coherence
of the various claims and doctrines that Goudge and others have found to
be in conflict. The best that can be done is to outline the basic
architecture of Peirce's philosophy and to give a glimpse of its overall
unity.
For Peirce, as for Kant, logic was the key to philosophy. He claimed
that from the age of twelve, after reading his brother's copy of
Whately's Elements of Logic, he could no longer think of anything except
as an exercise in logic. (21) Peirce's study of logic was not limited to
the formal theory of deductive reasoning or to the foundations of
mathematics, although he made important contributions to both. When he
sought the professorship of physics at the Johns Hopkins (before being
appointed part-time lecturer in logic), he wrote to President Daniel C.
Gilman that it was as a logician that he sought to head that department
and that he had learned physics in his study of logic. "The data for the
generalizations of logic are the special methods of the different
sciences," he pointed out, and "to penetrate these methods the logician
has to study various sciences rather profoundly."
But it was not just as a theory of reasoning or as a critique of methods
that logic was important for philosophy. "Philosophy," Peirce said,
"seeks to explain the universe at large, and to show what there is
intelligible or reasonable in it. It is therefore committed to the
notion (a postulate, which however may not be completely true) that the
process of nature and the process of thought are alike" (NEM 4:375).
Whether completely true or not, if philosophy seeks to explain the
universe at large, and if our explanations presuppose a rational
organization of the universe—which, otherwise, would hardly be
explicable at all—then we are, in effect, committed to the thesis that
the process of nature is (or is like) a rational process. Logic,
therefore, has more than heuristic value for philosophy.
It is important to bear in mind that when Peirce called himself a
logician — the first and perhaps only person to have his occupation
listed as "logician" in Who's Who — he was not thinking of himself as a
logical technician or as a logicist who views logic as the deductive
foundation for mathematics. Although his many contributions to technical
logic—including his 1881 axiomatization of the natural numbers, his 1885
quantification theory and introduction of truth-functional analysis, and
his life-long development of the logic of relations—have considerable
importance for the foundations of mathematics, his main concern was to
build an adequate theory of science and an objective theory of
rationality. His general conception of logic was closer to modern-day
philosophy of science, together with epistemology and philosophical
logic, than to today's mathematical logic. In his later years, Peirce
gave a great deal of attention to the classification and relations of
the sciences and he came to associate much of what we would today call
mathematical logic with mathematics; logic, on the other hand, he came
to regard as a normative science concerned with intellectual goodness
and, in his most developed view, it is coextensive with semiotic, which
constitutes the very heart of philosophy.
Source: http://www.iupui.edu/~peirce/ep/ep1/intro/ep1intrx.htm