Gemini LLM on direct realism. Part four. Enjoy!
Isn´t indirect realism self-contradictory? How can the indirect realist *know* that a straw bent in water isn´t real, if everything are just mental images? They seem to use one mental image to disprove another one!
You have hit on what many philosophers call the "Transcendental Objection" to indirect realism. It is a powerful critique that points to a fundamental "performative contradiction" in the theory.
The contradiction you are identifying is this: the indirect realist claims we only ever perceive mental representations, yet they frequently use physical facts (like the laws of refraction or the actual straightness of a straw) to explain why our perceptions are sometimes "wrong."
Here is how that contradiction is broken down and how indirect realists attempt to wiggle out of it.
1. The "Double Standard" of Evidence
As you noted, the indirect realist says: "I know the straw isn't actually bent because I know the laws of physics and the properties of wood."
The Problem: How does the indirect realist know the laws of physics or the "true" shape of the straw? According to their own theory, their knowledge of physics and "straight straws" also came to them via mental images.
The Contradiction: They are using "privileged" mental images (the ones they label as 'scientific' or 'accurate') to demote "deceptive" mental images (the bent straw). But if everything is a mental image, they have no objective "ruler" outside of their own mind to decide which image is the "true" one.
2. Coherentism: The Indirect Realist’s Defense
Most indirect realists (like John Locke or modern functionalists) try to solve this using Coherentism. They argue that we don't need to "step outside" our heads to find truth; we just need to see which images play well together.
Consistency: If I pull the straw out of the water, it looks straight. If I touch it, it feels straight. If I use a ruler, it measures straight.
The Argument: The "bent" image is a singular anomaly. The "straight" image is supported by a massive web of other sensory data (touch, memory, mathematics).
The Indirect Realist's Counter: They aren't using one image to disprove another; they are using a consistent system of images to identify an inconsistent one.
3. The Phenomenal vs. The Physical
Another way they avoid contradiction is by distinguishing between Primary and Secondary qualities.
Primary (The "Truth"): Extension, motion, number. These are "mathematical" and exist in the object.
Secondary (The "Representation"): Color, taste, "bentness." These exist in the mind.
The Logic: The indirect realist argues that they can "calculate" the truth of the world using the primary qualities (math/physics) even if their secondary qualities (the visual image) are wonky.
4. The "Brain in a Vat" Trap
If you push the indirect realist on your point—"How do you know there is even a straw at all?"—they eventually have to admit they don't know for certain.
This leads to the Skeptical Gap. If they are consistent, they must admit that their "scientific" view of the world is just a very useful, highly organized dream. If they claim to know the "real" world exists behind the image, they are making a "leap of faith" that their theory technically forbids.
Summary of the Conflict
Your Point: If we only see images, we have no "non-image" to compare them to.
The Indirect Realist Response: We compare images to other images and choose the most mathematically consistent ones.
The Direct Realist Response: Exactly! This is why indirect realism is a "prison." We should just admit we are seeing the straw itself, albeit through the medium of water.
Would you like to look at the "Coherence Theory of Truth" which many indirect realists use to justify their claims, or should we examine how "Scientific Realism" tries to bridge this gap?
We don't have enough "parts" to combine into a Coherent Indirect Realism. Or, we do not know all the materials and levels of material, including "higher vibrations", that exist and hence cannot have a Coherent understanding alone. But, in using Coherency as a pathway we may come around to bite our own tail and prove Scientific Realism in spite of ourselves.
ReplyDeleteHa ha, yes indeed. One of my problems with "indirect realism" is that we must have evolved to have *some* true perceptions of the world, otherwise we wouldn´t have survived! And like Gemini points out, having senses with direct access to the outside world has better survival value than simply seeing "mental images". Indeed, how could that even evolve, if there isn´t an immidiate connection to the outside world, as opposed to a after-the-fact rationalization known as "Coherentist Indirect Realism"? Could our ape-like ancestors really survive if they had been "Coherentist Indirect Realist" philosophers?
ReplyDeleteThe day our ape-men got bonked on the head by a rock, or got scorched by being a little too close to the fire they discovered Scientific Realism! Rock=hard Fire=hot! Our very physicality presumes that we are rooted in the "science". The "coherency" perhaps is what led to myths and religion.
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