Department of Philosophy
"Do Logical Inferences Preserve Truth?" (In Japanese) Philosophy of Science (1994), 27:69-82.
"Fictionalism in Logic; Modality, Truth, and Conservativeness."
PhD Dissertation, University of Southern California, 1995.
Abstract in Dissertation
Abstracts International (June 1995), 55(12A):3867-A.
"It is usually held that what
distinguishes a good inference from a bad one is that
the former is but the latter is not truth-preserving.
What is behind this view is the
basic assumption that whether a certain inference is
truth-preserving or not is a
genuine issue, an issue the answer to which is
determined objectively. This view
is called the realist view of logic. In this
dissertation the realist view of logic is
criticized and an alternative view is presented. The
alternative is called the
fictionalist view of logic. On this view, what makes a
logical system good is not
that its inferential rules are truth-preserving, but
rather that it has a certain
proof-theoretic property, called deductive
conservativeness. More specifically, it
is argued that if the inferential rules for the logical
operators involved in the
system are conservative over the deductive system which
is devoid of logical
operators, then the conservative system will have all
the virtues we expect in a
good logical system. It is shown however that insofar
as the system is
conservative, there is no way to determine whether its
inferential rules are
truth-preserving or not; thus the latter is simply
irrelevant to the goodness of the
logical system. To support this claim, the view that
the meaning of a logical
operator is determined not by its semantic properties
such as truth but by its
inferential role, is advocated. A significant
implication of this view is that there is
no answer to the question which of the conservative
logical systems is the
correct logic for the world. Furthermore, it is
maintained that metalogical claims
of implication and consistency, namely claims of the
forms 'A implies B', and 'A
is consistent', can be taken as modal claims which
involve modal operators as
logical operators, and thus the above approach is
applicable to such metalogical
claims, too. This idea is used to avoid our ontological
commitment to
mathematical entities such as models and proofs
employed in metalogic."
"Quine and the Linguistic Doctrine of Logical Truth." Philosophical Studies (June 1995), 78(3):237-256.
"Field on the Notion of Consistency." Notre Dame Journal of Formal Logic (1996), 37(4):625-630.
"Logic as Instrument: The Millian View on the Role of Logic." History & Philosophy of Logic (1996), 17(2):73-83.
"The Truth-Functional Theory of Conditionals." (In Japanese) Kumamoto Journal of Humanities Philosophy (1997), 54:42-58.
"Nominalistic Metalogic." Journal of Philosophical Logic
(February 1998), 27(1):35-47.
"On Super- and Subvaluationism: A Classicist's Reply to Hyde."
Mind (October 1999), 108(432):727-732.
Hyde (1997) introduced subvaluationism, a logical system for vague words that
employs paraconsistent logic, and maintained that
subvaluationism is substantially different from supervaluationism,
and is at least as good for a logic of vagueness.
In reply, this paper argues that subtruth in subvaluationism may
reasonably be taken not as truth simpliciter but as possible truth in a
certain sense of "possible", and that supertruth in
supervaluationism may likewise be taken as necessary truth.
It is shown that there is a plausible way of interpreting super- and
subvaluationism which integrates the two and validates classical logic.
Full-text from ECO
"Identity Is Simple." American Philosophical Quarterly (October 2000), 37(4):389-404.
"Indefiniteness of Mathematical Objects." Philosophia Mathematica (2000), 8(1):26-46.
"Logic and Truth: A Fictionalist View." Journal of Philosophical Research (2000), 25:101-123.
"Shogenji's Probabilistic Measure of Coherence is Incoherent."
Analysis (October 2000), 60(4):356-359.
Full-text from Ingenta
"Vagueness As a Modality."
Philosophical Quarterly (July 2000), 50(200):359-370.
Full-text from Ingenta
"Can Deflationism Allow Hidden Indeterminacy?" Pacific Philosophical Quarterly.
"A Deflationist Approach to Indeterminacy and Vagueness." Philosophical Studies.
Review of Terence Parsons' Indeterminate Identity: Metaphysics and Semantics. Philosophical Quarterly.