Monday, May 7, 2012

Universal Truth

I'm going to try to argue that The Last Superstition fails to make the case for Feser's preferred metaphysics. I want to be clear that I'm only attempting to address Feser's argument, as presented in this book. There might be a much more effective case to be made, and maybe it can be found in Aquinas, or in Feser's other books, none of which I've read. But he presents his case in this book as an (irrefutable!) logical argument for God, so that's how I'll treat it.

One of the first things Feser tackles is the problem of universals. This philosophical problem has a 2000 year history, and is still a matter of debate today. Yet Feser claims that conceptualism and nominalism, the major alternatives to  Feser's preferred realism, are demonstrably false. I guess none of those other philosophers were smart enough to see that the problem had already been solved.

As examples of universal, Feser lists "triangularity," "humanness," and "redness." And by realism about them, he means that they "exist objectively, apart from the human mind and distinct from any material or physical features of the world."

Now, redness is an interesting choice. We now know a lot more about color perception than Aristotle did. What we know as colors are the result of a complex interaction among the light source, the surface of the colored object, the physiology of the eye, and the processing that goes on in the brain.

Start with an obvious point: "red" is an English word. We can translate it into other languages - but can we be sure that the extent of "rot" in German (for instance) coincides with "red" in English? Maybe, and maybe not. But some languages don't have a word that even vaguely resembles "red." The Jale of New Guinea have only two color terms: roughly, "brilliant" and "dull." The Tiv of Nigeria have three color terms:

 ii, which encompasses all greens, some blues, and some greys; pupu, which encompasses very light blues, light greys, and white; and nyian, which encompasses red, some browns, orange and yellow.
When someone says "The apple is red (nyian)" in Tiv, they are saying something very different than I am when I say that sentence. So it is clear that color is a culturally dependent quantity.

Even within our own culture, people can differ about what a term means. "That's not red, that's maroon!" If twenty people looked at this chart and picked out the colors they would label "red," there might not be two lists that agree. And it's not just a matter of definition: people's perceptions of color can differ dramatically. This is most obvious in color blindness, but here's a personal example that doesn't involve color blindness. When my wife and I were house hunting, we discussed one house that had (my wife thought) beautiful green marble counter-tops in the kitchen. "They weren't green, they were black!" I exclaimed. And it wasn't just a matter of lighting or recollection: we now live in that house, and my wife maintains that we have green counter-tops (with black flecks), while I am sure that they are black (with some green in them).

But if you really want proof that colors are not mind-independent, just look at the following image:

Do you see the green and blue spirals? So do I: but there aren't any green and blue spirals. Those spirals are exactly the same color. (r = 0, g = 255, b = 150) That is to say, in every objective, measurable sense, they are the same. Yet our minds interpret them as different colors.

Imagine that an extraterrestrial lands on Earth. Its physiology is completely different from ours. Maybe it doesn't even perceive light: it gets around by some sort of sonar. How would you explain why an apple and a fire engine are both red? How would you explain why two of those spirals are green and the other two blue?

 It is clear, then, that colors are not mind-independent. But that at least leaves open the possibility that other things that seem obviously mind-independent are, in fact, mind-dependent.


  1. A consistent theme runs through Feser's work: he makes grand metaphysical pronouncements, and then dips his toe into science to try and justify his pronouncement. But he invariably gets the science wrong. I recall in a blog post he tried to make the case for the objective existence of "cold". It was both sad and hilarious. He does not even have a rudimentary understanding of physics.

  2. Not only Feser: I don't think any of those articles they linked to (over on the Reppert discussion) had any serious consideration of QM. A lot of detailed consideration of "local motion" (so the Thomists have now caught up with Galileo...), but no QM.

  3. "Those spirals are exactly the same color. (r = 0, g = 255, b = 150) That is to say, in every objective, measurable sense, they are the same. "

    How can you say that the two colors are objectively the same and then claim that colors are mind-dependent? I don't think an illusion proves anything. When a magician performs a levitation he doesn't really defy the laws a physics he just tricks our perceptions.

  4. According to Feser, your "red" example "is a bit like saying that since people used to think that 'the morning star' and 'the evening star' named different objects, it follows that the planet Venus is 'culturally dependent'."

    But Feser's Venus example is not *like* the color example. Venus is one planet. Redness is a band of frequencies. Redness is *not* one frequency. Each human has a slightly different *biological* collection of color receptors. My red receptors most likely do not respond to the exact frequency of light as Feser's. This is a biological fact. So a supposed universal for redness cannot be based on light itself. His only option is to posit "redness" is not about particular wavelengths of light (he tags "red"), it's about the specific biological mechanisms themselves and "redness" is whatever energizes them (he tags sensual "RED:). But then Feser will eventually have to start sounding something like the Churchlands and the "Eliminative materialism" Feser ridicules. It seems to me Feser slits his own throat while clumsily trying to save his universals.

  5. In reading Feser's response this jumped out at me.

    "For then we will still have a set of distinct kinds of red each of which is itself a kind of universal"


    "...every instance of RED in my sense of “RED” is an instance of the same one universal, and every instance of RED in your, different sense of “RED” is an instance of a different universal, and so forth."

    So a "universal" turns out to be a personal, custom "universal" to each of us no matter how Feser looks at it. This makes a laughingstock of the concept of universals. But how interesting that Feser would take this tact. In order to save the universal, redness becomes subjective.

    It follows that morality can be seen in the same way. Is there a universal for stealing? Well, yes as long as we have a set of distinct kinds of stealing each of which is itself a kind of universal. Feser's stealing, it turns out, does not have to exactly correspond to my stealing. That's what moral relativists have been saying -- probably because they made the mistake of rejecting universals. But somehow Feser with his universals reaches the same nasty end.

  6. I actually agree with Feser's defense in that Oerter didn't show universals don't exist, merely that many such would need to exist. One then needs to talk about the "hierarchy" and structure of the Platonic world of universals, and whether indeed the One of Neoplatonism makes sense, and can be identified with God. I think the whole project doesn't work, but discussing it and showing that is not the same as pointing out that there are actually lots of "red" universals.

    The more pointed critique of Feser was only given a brief paragraph. " Yet Feser claims that conceptualism and nominalism, the major alternatives to Feser's preferred realism, are demonstrably false. I guess none of those other philosophers were smart enough to see that the problem had already been solved." THAT is the real problem with Feser's position, that should be expanded and explored.


  7. As an avowed atheist I have to say this argument against Feser is flawed for the reasons given above by Joe.

    Furthermore, "Red" is universally known by physicists according to the wavelength, specific for whichever shade of red. Red is not a matter of perception--it has nothing to with the number of rods and cones in one's eye.

  8. Tony (and Joe), I think the illusion makes it perfectly clear that "red" (in ordinary usage) is NOT defined by any given set of wavelengths. If you want to define colors in terms of wavelength, what color do you assign to the wavelength represented in those spirals? Is it blue? Is it green?

    Of course, you can abandon the hope of capturing what "red" means in ordinary usage, and try to define it in purely physical terms. Then you run into a different problem: real objects don't reflect a pure wavelength - they display a continuous spectrum. (Look at slide 22 of this PowerPoint to see what I mean: )

    To define "red" in terms of wavelength, you would have to define a region in an infinite-dimensional parameter space. This is not only impossible, it is pointless, for the reasons I pointed out in the blog post: you would never get agreement on whether that region captures what people actually mean when they say "red."

    You can go further, and abandon any attempt to capture what people usually mean when they say "red," and instead simply DEFINE "color" to be "whatever electromagnetic spectrum an object reflects." But then you have to live with the consequences: no two objects are ever the same color (because no two spectra are ever exactly the same), the color of any given object is constantly changing (as lighting changes, or angle of viewing), "red", "blue", "green" are not colors, etc.

    Hence (if you take this last route) "color" is not longer a universal. There are only particular spectra of particular objects under particular lighting conditions. You can't rescue the universality of color this way.

  9. I am not a philosopher (a physician by training) but I think the concept of universal truths, from an Aristotelian sense as adopted by Aquinas, states that no matter what our perception, some objective concept exists for things like humanness, triangularity and redness. We may not have the ability to conceptualize these things, but they exist.

    At some point all philosophy becomes navel gazing, but Feser and theists in general are using this idea to "prove" that god exists. If an objective truth is necessary, then God. This goes beyond pointless navel gazing because this is an argument that theists not only believe that the true essence of reality has defined properties...but they *know* these defined properties because of a Revelation.

    And it's not just "red" or "triangularity", but it's also morality and truth. We can concede the point that universal truths exists, that objective reality is afterall objective, and I would even concede that if they want to name the author of all this objective reality "God", fine...but

    I have to stop there. I cannot accept that anybody can *know* the objective reality, and I certainly cannot accept that the Old Testament, or Jesus, or the Pope, et al, is the sole arbiter of all this reality because they have special access to "God" the author, which is where this argument is necessarily headed.

  10. You guys don't know that a scanner can discern colors and reproduce colors in a print even when humans are not around to look at the colors.

    So also a camera can record colors.

    You guys like the author of this blog make a lot of nothing exists but it is all in the mind, what about the traffic lights: try insisting that they don't exist and see whether you will not get hit by speeding vehicles when the red light says to stop crossing the street.


  11. odrareg, you seem to have massively missed the point. Look at the green and blue spirals. The scanner will tell you they are the same color.

    Of course there are objective properties of light that are mind-independent - I'm not claiming otherwise. But those objective properties do not map directly to what we call color (as in the blue and green spirals). See my post about wavelengths of light and color just above.

    And what happens when you run a red light has little to do with the physical properties of light and a lot to do with cultural expectations and practices - all of which are very mind-dependent.