Comments on “Clouds and eggplants”

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Joseph Ratliff 2018-09-02

Excellent overview, and thanks for defining these terms.

I hope “The Eggplant” gets printed in paperback, because I have a feeling it’s going to be a book I want to keep on my shelf.

Paperback version

David Chapman 2018-09-02

Thank you! Yes, I’m planning a paperback version of it.

Unconverted links

Nick Hay 2020-06-21

In case you’ve missed them, there are a few instances of unconverted links like [itcote] and [teggplant] through the text.

I need a continuous integration pipeline apparently

David Chapman 2020-06-21

Thank you! The code for expanding those got lost a few days ago in a write-write conflict, when I changed my workflow for editing the server code and forgot what I was supposed to do.

Fixed now. But I need to get more serious about standardizing the workflow.

Tautology alert?

Robert 2020-08-08

“nebulosity is pervasive. … nothing is ever definitely this-or-that.”
“Facts about eggplants are inescapably indefinite, due to nebulosity.”

This looks like a tautology to me… nebulosity arises from indefiniteness and vice versa…

Indefinite explanation

David Chapman 2020-08-12

Thanks; I deleted the sentence. There’s a relationship between the indefiniteness of statements and the indefiniteness of objects that I had in mind; but this was not the place to explain that!

Mathematics and fundamental physics

Olga 2020-09-02

I would really love some explanation why mathematics and fundamental physics are singled out, but that may be better suited to another part of the book.
At this moment I guess it’s because mathematics is a meta activity for formally manipulating patterns, which doesn’t deal with actually finding and defining patterns in the real world and separating them from nebulosity; and fundamental physics to the best of our current knowledge is stripped of all context and due to its scale is so granular that it doesn’t have nebulosity?


David Chapman 2020-09-02

Thanks, excellent question!

The reason for singling them out is that if you say “there are no absolute truths,” rationalists immediately say “you are badly wrong, mathematics and particle physics are absolutely truly true.” They do have a point, although whether it’s actually correct is unclear.

What’s important is that it’s almost always an irrelevant distraction, because even if mathematics and particle physics are absolutely true, that absoluteness can’t be extended to encompass facts about breakfast-sized phenomena. In other words, reductionism mostly doesn’t work.

So acknowledging that “maybe those truths are absolute” saves one from getting into pointless metaphysical arguments.

There is some sense, at least, in which some mathematical truths, such as 2+2=4, are absolute. There was a recent massive twitter brawl about this. It generated much more heat than light, but did bring up some interesting points. Many serious mathematicians came down on the side of “not necessarily absolutely true, depending.” I made a small contribution in a thread starting at:

So even small-integer arithmetic may be somewhat nebulous in some sense. It seems to be a different sense than the nebulosity of breakfast, however.

Similarly, experiments showing measurements agreeing with quantum theory to a dozen decimal places suggest that there’s some sense in which something like it is really truly true. On the other hand, we know the current theory can’t be right, and also it’s not clear what “really truly true” would mean. And, more importantly, even if a version of quantum theory were absolutely true, that doesn’t seem to have any meaningful implications even for most of the hard sciences. Even in chemistry, reduction to quantum is mostly not possible in practice, and probably never will be.

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