Instrumentalism

Instrumentalism is one of a multitude of modern schools of thought created by scientists and philosophers throughout the 20th century. Its premises and practices were most clearly and persuasively stated by two philosophers—John Dewey (1859-1952) and Karl Popper (1902-1994). Independently, they defined the school quite similarly, but their judgments of it were irreconcilable.

Dewey was a practitioner of instrumentalism. He insisted that modern scientific inquiry requires both induction and deduction, while denying its capacity to uncover realities independent of experience. Popper was a critic of the school. He insisted that induction is not scientifically valid, and that realities can be known without experience. These contrary judgments endowed the school with the legacy of confusion and ambiguity described below.

This article reports the definition of instrumentalism accepted by these two philosophers. It explains the grounds of their irreconcilable judgments, which are still embedded in popular understanding of the school. And it describes the practice of followers of each philosopher, demonstrating that neither philosopher's judgments have achieved universal assent, leaving the school's meaning and legitimacy in modern scientific inquiry indeterminate.