Because I believe we can do far better than nominalism. — Olivier5

I think Isaac's point is that you are doing nominalism, you're just calling it idealism.

But non-eucledian triangles are still called triangles. — Isaac

Oh. Didn't know that.

It's not similar enough for their current purpose to the definitions the rest of their language community are using. — Isaac

Fair enough.

No, not at all. I've demonstrated above that there is no such idea. Just several ideas which share common features. — Isaac

Sure. The goal of my comment wasn't to defend the universality of certain ideas, but the existence of ideas. A largely similar idea of "New York" exists. And that idea is not material. Though not a separate substance either.

All we do, intellectually, is move back and forth from observation, to inter-subjective validation, to concepts and communicable narratives using those concepts. One can try to discard this as "a tune already played", but this little tune is us, from the cradle to the grave, so one would only be discarding oneself...

Isaac has a history of not understanding what I say very well, so it would not come as a surprise if he did misunderstand me once again.

So, even though

Triangles, letter 'A's, some multiple of similar objects, a city... these are all postulates, models of the causes of the sensations we receive. The same is true of thoughts. Thoughts are all recalled post hoc. ....

So when I talk about what 'ideas' really are, I mean to refer to a model of their hidden states. What causes the sensation that I'm possessed of an 'idea'. My model for that is that of neurons being in certain configurations and having reached threshold levels of activation — Isaac

But nevertheless,

I use my a priori methods of inference — Isaac

So, this 'hidden states model' is not applicable to scientific reasoning? By what criterion do you distinguish scientiific judgements from the ordinary neural activities which you say comprise mental life, and are based on a model of the mind's hidden states?

It does seem to me that:

Like all naïve materialists, you are sawing the conceptual branch on which you sit. — Olivier5

When you understand a logical principle, or algorithm, say, to make a prediction, or solve some arcane mathematical conjecture - how can this be possibly be categorised as a ‘sensation’?
— Wayfarer

I thought I'd just explained that. 'Understanding' a thing is a post hoc model of the actual link between sensation and response. We can prove this by lesion experiments, as I've described. So one senses, by interoception, that one is possessed of an idea. You may be limited by thinking of senses as being just the five we're taught about in primary school. This is just a simplification for children. There's scores of 'senses'. — Isaac

Any examples of what these additional senses are, over and above the five we're taught at school?

I can give one example off the top of my head, though it's probably not useful to Isaac's point: proprioception, our internal sensation of where our bodies are in space. It's how you can (unless you're too drunk) touch your opposite index fingers together with your eyes closed: you have a mental model of where in space your body is as you move, informed by feedback from your joints etc.

Any examples of what these additional senses are, over and above the five we're taught at school? — Wayfarer

Isaac mentioned "interoception". I would add "introspection" as a major one. There are others (e.g. the sense of balance).

Now that the debate is over and this thread has little to do with the debate, I've moved this discussion to a thread I named "What is Philosophy?" because I couldn't arrive at a better title. I'll be happy to change it to whatever you'd like though.

You can find the thread here: here