Mind-Brain Identity Theory Mind-Brain Identity Theory (also called Type Physicalism) asserts that mental states and processes are completely identical to physical states and processes in the brain (Smart, 2007). According to this theory, a mind is not a separate spiritual substance. Instead, experiencing an emotion or having a thought is literally the exact same thing as a specific cluster or kind of neurons firing. As such, mind-brain identity theory can be considered the exemplar of materialism. Early on, in the mid-20th century, mind-brain identity theory was a leading explanation of consciousness, but today, in its original form, it is no longer a major contender. Though the original identity theory has evolved in a kind of arms race with critics, it is generally considered undermined by various objections, the most common being multiple realizability (Aranyosi, n.d.). Mind-Brain Identity Theory core concepts: Strict Identity: The theory uses "identity" in an absolute literal sense. It is not saying the brain causes the mind, or that the mind depends on the brain. It means, literally, Mind = Brain. The Lightning Analogy: Philosophers explain this using scientific discoveries. We discovered that "lightning" is identical to an "electrical discharge." Likewise, “water” and “H2O.” They are not two different things; they are one phenomenon described in two ways. Identity theory claims the same is true for "pain" and "brain fiber firings." Historical Pioneers: The theory was developed in the late 1950s by philosophers U.T. Place, Herbert Feigl, and J.J.C. Smart. They wanted a philosophy that aligned with modern, materialist science. As noted, its central challenge is multiple realizability. The biggest and most famous objection to Identity Theory came from philosopher Hilary Putnam in the 1960s. He made the following argument: Identity theory claims a specific mental state (like "feeling pain") is identical to a specific human brain state. The Problem: An octopus or an alien could clearly feel pain, but their brains are anatomically entirely different from humans. The Conclusion: If an octopus can feel pain without having human brain structures, then "pain" cannot be identical to just one specific type of human brain state. This objection led many philosophers to abandon Identity Theory and move toward Functionalism. I/RLK take special interest in identity theory, especially for Landscape, not because I subscribe to the early mind-brain identity theory as originally formulated, but because I see its way of thinking as far more pervasive and far more elucidating than often realized (though perhaps in a way not as sanguine as some may have hoped). I would want to generalize classic mind-brain identity theory’s commitment that mental states/events/processes are identical to brain states/events/processes. I would want to say that any theory of consciousness, to be complete and sufficient, must make some kind of an identity claim. Bottom line, every theory of consciousness that offers itself as a total explanation, necessary if not always sufficient, must be a kind of identity theory. I mean identity theory in the strong sense, in the same sense that the Morning Star and the Evening Star must both be Venus, such that if you eliminate the Morning Star you cannot have the Evening Star. (David Papineau makes a virtue of this necessity in his mind-brain identity argument for physicalism [Papineau, 2020b]). It doesn't matter which specific materialist/physicalist or nonmaterial/nonphysical theory—all of them, in essence, are mind-brain identity theories. Here's the point. Everywhere there is consciousness, there is some kind of “consciousness identity” actually happening—it is always happening and it never changes. Something happening or existing in every sentient creature just is consciousness. References Aranyosi, István. Mind-Brain Identity Theory. PhilPapers - https://philpapers.org/browse/mind-brain-identity-theory. Papineau, David. (2020b). We must shed our metaphysical assumptions Instit. Art Ideas. https://iai.tv/articles/we-must-shed-our-metaphysical-assumptions-auid-1367. Smart, J.C. (2007J. The mind/brain identity theory. Edward N. Zalta, Uri Nodelman (Eds.), The Stanford Encyclopedia of Philosophy (Winter 2022 Edition) - https://plato.stanford.edu/archives/win2022/entries/mind-identity/.