Herbert Feigl

Quick Facts

• Name: Herbert Feigl
• Lived: 1902-1988
• Born: Reichenberg, then in Austria-Hungary; now Liberec, Czech Republic
• Worked mainly in: Austria and the United States
• Main fields: Philosophy of Science, Analytic Philosophy, philosophy of mind
• Best known for: logical empiricism, scientific realism, and the mind-brain identity theory
• Institutional role: founded the Minnesota Center for Philosophy of Science in 1953

The Big Question

Can a scientific picture of the world be both empiricist and realist?

Feigl wanted philosophy to stay close to testable science. But he did not think this meant treating atoms, fields, or brain processes as mere shorthand for what we observe. His central question was how science can talk about unobservable things while still being answerable to evidence.

In One Minute

Herbert Feigl was an Austrian-American philosopher who helped bring the Vienna Circle's logical empiricism into American philosophy. Logical empiricism says philosophy should clarify scientific concepts, reject empty speculation, and ask how claims connect to evidence.

Feigl also pushed logical empiricism in a realist direction. Scientific realism says that successful science often tells us about real things we cannot directly see, such as atoms or electromagnetic fields. Feigl argued that these terms do not merely summarize observations. They refer to parts of the world that help make observations happen.

In philosophy of mind, Feigl defended a version of the mind-brain identity theory. The theory says that mental events, such as pain or seeing red, are not ghostly events beside the brain. They are the very same events described in a different vocabulary: one from first-person experience, the other from neuroscience.

What They Taught

Feigl taught that philosophy should serve science by making its concepts clear. A philosopher should ask what a theory says, what would count as evidence for it, how its terms refer, and where it drifts into unsupported metaphysics. He inherited this style from Moritz Schlick, Rudolf Carnap, and the Vienna Circle.

But Feigl was never comfortable with the idea that science only reports actual or possible experiences. Early logical positivists often used a strict verification test: a statement is meaningful only if it can be verified by observation or logic. Feigl came to prefer the looser term logical empiricism because scientific theories are not verified in that simple way. They are tested, confirmed, revised, and connected to observation through long chains of inference.

This mattered for theoretical terms. A theoretical term is a word used by a theory for something not directly observed, such as an atom, an electron, a force field, or a neural process. Feigl argued that such terms can refer to real things. The word "atom" does not mean "a pattern in my sense data." It refers to atoms, if the theory is well confirmed.

His name for this approach was often semantic realism. "Semantic" means about meaning and reference. Evidence is what supports a claim. Reference is what the claim is about. Tracks in a cloud chamber are evidence for electrons. But "electron" refers to electrons, not to the tracks.

Feigl used the same distinction in the mind-body problem. The mind-body problem asks how conscious experience relates to the physical body and brain. Feigl rejected dualism, the view that mind and body are two separate kinds of stuff. He also rejected crude behaviorism, the view that talk about mind can be reduced to talk about outward behavior.

His answer was identity theory. A pain, a color experience, or a feeling is not merely caused by a brain process in the way smoke is caused by fire. It is the same event described in two ways. From the inside, you say "I feel pain." From neuroscience, the same event may be described as a process in the central nervous system.

This is why Feigl liked "double-language" or "double-knowledge" language. There are two ways of knowing the same event. First-person experience gives direct acquaintance with the pain. Scientific description gives an indirect public account of the neural process. The difference is in how we know and describe it, not in there being two separate realities.

Key Ideas With Examples

• Logical empiricism: Philosophy should clarify scientific language and reject claims that cannot be tied to evidence. Example: instead of asking whether "the Absolute" is beyond experience, Feigl asks what claim is being made and what could confirm it.

• Scientific realism: Good scientific theories can describe real unobservable things. Example: atomic theory explains and predicts enough that "atom" should be treated as referring to real atoms, not just to laboratory effects.

• Semantic realism: Meaning includes reference to what a term is about, not only the observations that support it. Example: a thermometer reading is evidence for temperature, but "temperature" does not mean "thermometer reading." It refers to a physical condition of a system.

• Theoretical terms: These are words used inside scientific theories for things or structures that are not directly observed. Example: "electromagnetic field" is not a name for a sensation. It is a theory term for a physical field, if the theory is correct.

• Confirmability instead of simple verification: Many scientific claims cannot be proved by one observation, but they can be supported by evidence. Example: many connected experiments can make atomic theory strongly confirmed.

• Mind-brain identity theory: Mental events are identical with brain events, though described differently. Example: the felt burn of pain and the relevant neural process are one event under two descriptions.

• Raw feels: Feigl used this phrase for the immediate feel of experience, such as pain or the look of red. He did not deny raw feels. He argued that they can be physical without being reduced to outward behavior.

• Nomological danglers: This was Feigl's nickname for mental events or laws that "dangle" outside the physical causal order. Example: if a separate mental pain is caused by the brain but causes nothing back, it becomes an idle extra. Feigl thought identity theory gives a cleaner account.

Major Works

• Theory and Experience in Physics (1929): Feigl's early book on how physical theories relate to experience. It shows his resistance to reducing physics to sense data.

• "Logical Positivism: A New Movement in European Philosophy" (1931, with Albert E. Blumberg): An early English-language introduction to the Vienna Circle's program, centered on logic, science, and the rejection of empty metaphysics.

• "Sense and Nonsense in Scientific Realism" (1936): Feigl's early statement of the problem of realism: are theories useful instruments, or do they tell us what the world is like beyond direct observation?

• "Existential Hypotheses" (1950): A major statement of Feigl's semantic realism. Claims about theoretical entities can be meaningful and confirmable without being translated into claims about immediate experience.

• "The 'Mental' and the 'Physical'" (1958; expanded with a postscript in 1967): Feigl's best-known work. It gives his mature account of evidence and reference, raw feels, and the identity of mental events with neurophysiological events.

• Readings in Philosophical Analysis (1949, co-edited with Wilfrid Sellars) and Readings in the Philosophy of Science (1953, co-edited with May Brodbeck): Anthologies that helped define mid-century analytic philosophy and philosophy of science in the United States.

Why It Matters

Feigl matters because he shows that logical empiricism was not only a narrow verification slogan. In his hands it became a disciplined way to defend realism, theoretical science, and a scientific approach to the mind.

His philosophy of science helped make room for a view many philosophers now take seriously: science can be empirically responsible while still talking about real unobservable structures.

His philosophy of mind helped launch modern physicalist debates about consciousness. Physicalism is the view that minds belong to the physical world. Feigl's version is more careful than a simple "the mind is just behavior" view. He took first-person experience seriously, but he denied that it requires a second nonphysical substance.

Feigl also mattered institutionally. At the University of Minnesota he founded the Minnesota Center for Philosophy of Science, which became a major home for work on probability, explanation, theory structure, mind, and method.

Proponents, Critics, and Opponents

Feigl was shaped by Moritz Schlick, especially Schlick's realism and double-language approach to mind and body. He shared Rudolf Carnap's concern for logical clarity, but moved more openly toward realism about theoretical entities.

Albert Einstein mattered as a model of realist scientific thinking: modern physics could force philosophy to take invisible structure seriously without leaving empirical science behind.

In philosophy of mind, Feigl is often grouped with U. T. Place and J. J. C. Smart. They also defended mind-brain identity theory in the 1950s. Feigl's version was distinctive because he stressed reference, first-person evidence, and raw feels.

Critics pressed Feigl from several sides. Some logical empiricists thought his realism added little to empiricism. Dualists argued that conscious experience cannot be identical with brain processes. Later critics of type identity theory argued that the same mental state might occur in creatures with very different physical structures. Feigl's reply would start from modesty: philosophy can clear the concepts, but the detailed identities must be investigated by science.

Related Pages

• Moritz Schlick
• Rudolf Carnap
• Albert Einstein
• Philosophy of Science
• Analytic Philosophy
• Philosophy of Technology and AI