The Philosophy of C. I. Lewis – Pragmatism, Logic, and the Foundations of Knowledge | The Library of Living Philosophers | Volume XIII, 1968 | Review, Analysis & Summary

The Philosophy of C. I. Lewis, compiled by Paul Arthur Schilpp, represents Volume XIII in the esteemed Library of Living Philosophers series, released in 1968. This work honors Clarence Irving Lewis (1883–1964), an innovative American philosopher celebrated for formulating conceptual pragmatism, advancing modal logic, and making notable contributions to 20th-century epistemology.
This volume includes an extensive philosophical autobiography, excerpts from Lewis’s key writings, critical analyses from noted philosophers, and Lewis’s reflective responses, rendering it essential for those exploring American philosophy, logic, or knowledge theories.

Who Was C. I. Lewis?

C. I. Lewis was a prominent American philosopher, educator, and logician. Frequently acknowledged as the originator of contemporary modal logic, Lewis taught for an extended period at Harvard University, where he impacted numerous philosophers, such as Willard Van Orman Quine, Nelson Goodman, and Roderick Chisholm.
The crux of Lewis’s philosophical pursuits encompassed:

• Epistemology, focusing on knowledge theories
• Logic, especially modal and symbolic logic
• Ethics and value theory
• A distinct integration of American pragmatism with analytic philosophy

His most notable works include:

• A Survey of Symbolic Logic (1918)
• Symbolic Logic (1932, co-authored with Cooper Harold Langford)
• Mind and the World Order (1929)
• An Analysis of Knowledge and Valuation (1946)

Structure and Contents of the Volume

This LLP volume adheres to the established series structure, blending personal insights with academic discussion:

1. Philosophical Autobiography

In this reflective essay, Lewis details his intellectual journey—from his initial fascination with pragmatism and logic to his later contemplations on experience, knowledge, and value. He highlights his intellectual influences from Kant, Peirce, James, and Dewey while providing personal perspectives on his own pedagogical and literary practices.

2. Key Philosophical Writings

Excerpts from Lewis’s works demonstrate:

• The framework of conceptual pragmatism
• His pivotal contributions to modal logic and analytic philosophy
• The interplay between experience, meaning, and value
• His views on how concepts play a crucial role in forming knowledge

These writings emphasize Lewis’s dedication to rational exploration, ethical understanding, and the personal aspect of philosophical inquiries.

3. Critical and Interpretive Essays

A compilation of essays by leading philosophers, featuring:

• Willard Van Orman Quine – discussing language and logic
• Nelson Goodman – exploring epistemological foundations
• Contributions from Roderick Chisholm, A. C. Ewing, Brand Blanshard, and others

These analyses critically examine Lewis’s perspectives on:

• A priori versus empirical knowledge
• Conceptual frameworks and their meanings
• The essence of value philosophy
• The framework of ethical judgments
• The relevance of modal logic to analytic philosophy

4. C. I. Lewis’s Replies

In the concluding section, Lewis addresses his critics individually. His responses are succinct, insightful, and illuminating, demonstrating a thinker deeply engaged with the philosophical discourse and devoted to the pursuit of truth with both humility and diligence.

Key Themes in C. I. Lewis’s Philosophy

1. Conceptual Pragmatism

Lewis proposed a perspective he termed conceptual pragmatism, which posits that knowledge is influenced by conceptual frameworks selected for their practical applicability and predictive reliability. This approach synthesizes Kantian epistemology with American pragmatism, suggesting that the a priori is not static but develops from human decisions regarding conceptual frameworks.

2. A Priori Knowledge and Empirical Experience

Lewis reconceptualized the a priori as not being knowledge separate from experience, but as the structural principles we adopt to render experience comprehensible. To Lewis, concepts serve as instruments, and philosophy ought to examine how these instruments direct cognition and behavior.

3. Symbolic and Modal Logic

Lewis played a critical role in revitalizing interest in modal logic, presenting systems that explored necessity, possibility, and implication. His advancements established a basis for contemporary modal and deontic logic, influencing various disciplines, including philosophy and computer science.

4. Ethics and Value Theory

In his later works, Lewis focused on inquiries related to value, morality, and significance. He asserted the existence of objective moral values grounded in human experience and rational thought, rejecting both moral relativism and authoritarian views.

5. Meaning, Language, and Knowledge

Lewis’s perspectives on meaning suggest that comprehension results from logical structure and empirical validity. He underscored the knower's dynamic role in interpreting the world, a stance that would significantly impact constructivist and contextualist epistemology.

Why This Volume Matters

The Philosophy of C. I. Lewis is crucial for:

• Students involved in American philosophy and pragmatism
• Academics researching analytic epistemology and modal logic
• Scholars examining the progression of 20th-century logic
• Individuals investigating the convergence of ethics, meaning, and knowledge

This volume serves both as a homage to an influential thinker and as a paragon of intellectual engagement within modern philosophy.