Quine’s Dictum: Ontological Commitment in Logic

Understanding Quine’s Dictum

W.V.O. Quine’s famous dictum, “To be is to be the value of a variable,” is a cornerstone of his philosophy of language and ontology. It provides a criterion for determining what entities a theory is committed to existing.

The Core Principle

The dictum asserts that our ontological commitments are revealed by the variables in our most rigorously formulated theories, particularly in first-order logic. If a theory, when formalized, requires quantification over a certain type of entity for its statements to be true, then that theory is committed to the existence of those entities.

Implications for Existence

Quine argued against abstract entities like Platonic forms or universals unless they are indispensable to our best scientific theories. The dictum thus serves as a tool for philosophical analysis, helping to clarify what we are claiming to exist when we make assertions.

Formalization and Quantification

The emphasis is on the variables that are bound by quantifiers (like ‘for all’ or ‘there exists’) in a formalized language. For instance, a theory that states ‘There exists an x such that x is a prime number greater than 100’ is ontologically committed to the existence of prime numbers.

Debates and Criticisms

While influential, Quine’s dictum has faced scrutiny. Critics question whether it fully captures all senses of existence or if it unduly privileges scientific discourse. However, it remains a powerful heuristic for understanding the relationship between language, logic, and reality.