### Interesting xkcd Post

Because of the error it makes. Certainly, whatever space-time is, it is not a set of equations, which are themselves just a model, or "analogy," if you like, for space-time. We can, for instance, move our bodies through space-time, which we cannot do through a set of equations.

1. You obviously read the comic differently than I did. To me, the whole point is that the equations *are* an analogy (the key to this reading being the parallel uses of "like").

2. Yes, shonk, I see that angle, but it also seems like there is an implication that equations are closer than all other analogies.

3. Idealism/nominalism corrupts true science... again...

This article really opened me up to the vicious circle formulation of the 1st Law. He quotes this insightful passage from Eddington's The Nature of the Physical World:

Unfortunately in that case [of external forces acting on it] its motion is not uniform and rectilinear [as it would be if the 1st Law applied]; the stone describes a parabola. If you raised that objection you would be told that the projectile was compelled to change its state of uniform motion by an invisible force called gravitation. How do we know that this invisible force exists? Why! Because if the force did not exist the projectile would move uniformly in a straight line. The teacher is not playing fair. He is determined to have his uniform motion in a straight line, and if we point out to him bodies which do not follow his rule he blandly invents a new force to account for the deviation. We can improve on his enunciation of the First Law of Motion. What he really meant was--" Every body continues in its state of rest or uniform motion in a straight line, except insofar as it doesn't ". . . The suggestion that the body really wanted to go straight but some mysterious agent made it go crooked is picturesque but unscientific.

4. Alan, I'm not clear why you associate idealism and nominalism in this way, as idealist are often anti-nominalists. Berkeley of course was an idealist and a nominalist, but Plato was an idealist and quite anti-nominalist.

1. Nominalism is saying something is what we call it.

2. Right. Which is not what idealism is.

5. What modern idealists are not nominalists or vice versa?

6. Well, first off, let me ask who you consider to be a modern idealist? And are you talking epistemological idealism or ontological idealism?

In any case, Wikipedia seems to think idealism *implies* anti-nominalism:

Idealism
See also: German Idealism, Immanuel Kant, Johann Gottlieb Fichte, Friedrich Wilhelm Joseph Schelling, Georg Wilhelm Friedrich Hegel, and British Idealism

"Idealism is a broad category that includes several diverse themes, from Kant's radical doubt about what can truly be perceived externally to Hegel's Absolute Ideal at the verification of the sum of potential manifestations of matter and concepts. This position argues that the nature of reality is based only in our minds or ideas. The external world is inseparable from the mind, consciousness or perceptions. Universals are real and exist independently of that on which they might be predicated."

I think that's a bit strong, but it certainly shows that there is no necessary connection between the two things.

7. C. S. Peirce writes this on nominalism versus realism in his Collected Papers I.16:

"16. In the days of which I am speaking, the age of Robert of Lincoln, Roger Bacon, St. Thomas Aquinas, and Duns Scotus, the question of nominalism and realism was regarded as definitively and conclusively settled in favor of realism. You know what the question was. It was whether laws and general types are figments of the mind or are real..."

So, this comic illustrates many peoples' nominalistic conception of scientific laws, which are equations.

8. Also, I would consider almost every major modern philosopher following Descartes footsteps an idealist.

And what do you mean by "epistemological idealism or ontological idealism"? I have never seen that distinction before. How is it made? Thanks

9. Hmm, you've lost me now, Alan. I thought:
1) we were discussing the relationship between idealism and nominalism; and
2) the mistake I read in the comic was taking the equations as *more real* than space and time themselves -- a sort of hyper-realism.

10. "Also, I would consider almost every major modern philosopher following Descartes footsteps an idealist."

Well, you'd be alone in that consideration: I think you are using idealism in an odd sense.

'And what do you mean by "epistemological idealism or ontological idealism"?'

Rorty is an epistemological idealist -- all that we *know* is our own thoughts -- but an ontological materialist -- what's real is fundamentally matter. Kant is an epistemological idealist as well.

Berkeley, Bradley, Green, Bosanquet, and Collingwood were epistemological realists -- our thoughts know the real world -- but ontological idealists -- that real world is primarily mental. (That does not mean *just in my mind*, however!)

11. Let's do a rundown, talking ontological position -- this is just my understanding, and my degree of knowledge of these philosophers varies quite a bit:

Descartes: dualist
Locke: dualist
Berkeley: idealist
Leibniz: dual-aspect monist
Spinoza: ?
Kant: ontological nihilist (complete epistemological idealism), at least as of the Critique of Pure Reason
Hegel: idealist
Schelling: idealist
Marx: materialist
Nietzsche: ?
Russell: dual-aspect monist?
Fodor, Quine: materialist
Davidson, Searle: emergent properties materialist
Churchlands, Dennett: eliminative materialists

12. We can, for instance, move our bodies through space-time, which we cannot do through a set of equations.

I just smashed through E=mc^2 like the Kool Aid man. So there.

13. Anonymous7:34 PM

(smash)

"Ohhh-Yeah!!!"

14. I define nominalism in accordance with the C. S. Peirce quote I posted at 2:29 AM above, namely, that "laws and general types are figments of the mind." Is this definition too similar to that of idealism? Realism would say that "laws and general types are NOT figments of the mind."

I still do not understand the epistemological versus ontological idealism distinction. Is not something real inasmuch as it is intelligible, either in itself or relative to us?

1) we were discussing the relationship between idealism and nominalism; and

Yes, hopefully we can clear that up. :)
We need a more precise definition...

2) the mistake I read in the comic was taking the equations as *more real* than space and time themselves -- a sort of hyper-realism.

In what sense are space and time real, though? Is not space simply a relation between material bodies, and isn't time simply a measure of change in the relation between bodies?

So, yes, I agree that the reality of space and time and the equations that describe them, what ever it is, must be the same.

15. "I define nominalism in accordance with the C. S. Peirce quote I posted at 2:29 AM above, namely, that "laws and general types are figments of the mind." Is this definition too similar to that of idealism?"

Well, no, Alan, an idealist like Berkeley *might* have believed that -- I'm not sure he'd put it that way -- but that has nothing to do with idealism per se.

"Is not something real inasmuch as it is intelligible, either in itself or relative to us?"

Interestingly, *that is* an idealist position. (Hegel held something very much like that in saying "The real is the rational.") It turns out you are an idealist, Alan. Welcome! (I am a member of the British Idealists Association -- I can send you an application. :-)

16. I certainly don't consider myself an idealist because I believe that the universal concepts in our immaterial intellects are abstracted from sense data (the Peripatetic axiom that "Nothing is in the intellect that is not first in the senses."). The intellect knows the universal whereas the senses know the particular. The intellect abstracts the universal from the mental images received through the senses, divesting them of all that individuates them. The senses and intellect are passive; they do not create reality.

Descartes's res extensa / res cogitans dichotomy divorced the senses from intellection, the body from the mind. Because of this, the mystery needlessly arises of the correspondence between our thoughts with reality—and whether objective reality even exists.

I agree with Hegel provided his definition of what is real does not deny objective reality.

Rorty is an epistemological idealist -- all that we *know* is our own thoughts
What do you mean by "thoughts"? Mental images (individual, material) and/or ideas (in the sense of immaterial, universal concepts)?

-- but an ontological materialist -- what's real is fundamentally matter.
So Rorty thinks our thoughts are a type of matter? If so, he denies the reality of universal concepts, and this is nominalism.

Kant is an epistemological idealist as well.
For Kant, do the senses play any role in knowledge?

Berkeley, Bradley, Green, Bosanquet, and Collingwood were epistemological realists -- our thoughts know the real world
But not just the real (mind-independent) world, right? Our intellects can certainly reflect on themselves, as we are doing right now! :)

-- but ontological idealists -- that real world is primarily mental.
What exactly do you mean by mental? Dependent on a human mind or simply rational/intelligible?

Thanks

1. "But not just the real (mind-independent) world..."

There is no mind-independent world!

2. I think Oakeshott clears this up a lot, at least for me, in the beginning of Experience and it's Modes:

"'Experience' stands for the concrete whole which analysis divides into 'experiencing' and 'what is experienced.' Experiencing and what is experienced, are, taken apart, meaningless abstractions... perceiving, for example, involves a something perceived. "

He goes further:

"These two abstractions stand to one another in the most complete interdependence; they compose a single whole."

What Oakeshott seems to be doing is showing the rather obvious inability to have an experience without a subject of an experience, and likewise, the impossibility of having a subject of experience without something doing the experiencing. We can, for *analytical* purposes, remove one from the other, but we cannot, in actuality, do so, for the question What are you experiencing? becomes impossible without the object of experience, and secondly, the object of experience becomes impossible without something doing the experiencing. When we attempt to think of a tree existing outside the world of experience, we fail, because we are, right now, experiencing said tree in our own minds.

What Oakeshott is doing, I think, is trying to make folks understand that both the subject of an experience and the object of the experience are interdependent in the way that one cannot understand or conceptualize one without the other, much like how we would not understand the difference between "Up" if we did not know the "Down", or the idea of marriage without a having a spouse.

Whew! Tell me if I am wrong with any of this, Gene, but so far I think I am understanding Idealism the more I read and re-read Experience and it's Modes.

3. Yes, that is right, Alex. And *this* is what Berkeley was trying to say, not what Stove attributed to him.

17. "I certainly don't consider myself an idealist because I believe that the universal concepts in our immaterial intellects are abstracted from sense data (the Peripatetic axiom that "Nothing is in the intellect that is not first in the senses."). The intellect knows the universal whereas the senses know the particular. The intellect abstracts the universal from the mental images received through the senses, divesting them of all that individuates them. The senses and intellect are passive; they do not create reality."

But Alan, nothing you have said is contra idealism.

You seem to have some passing familiarity with idealism. But I did my PhD thesis on an idealist, and have written papers on others. Will you believe me when I tell you that you have a mistaken impression of what idealism means?

18. "What exactly do you mean by mental? Dependent on a human mind or simply rational/intelligible?"

Yes, here's one thing I can clear up quickly: Only epistemological idealists think the world is dependent on the *human* mind. Most idealists over time have thought reality is a world of ideas, but that those ideas are independent of any human mind -- it is God, or "the Absolute," or something like that, that constitutes the ultimate reality.

If you would like to read a paper that might clarify this, shoot me an e-mail: gcallah@mac.com.

19. Gene,

Could I email you as well to get some clarification on this...? I am deep in the fantastic Experience and It's Modes, and I continue to get questions and seek answers from other Idealists; this might be helpful!

20. Awesome! Thank you!