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Jack comments on Making Beliefs Pay Rent (in Anticipated Experiences) - Less Wrong

110 Post author: Eliezer_Yudkowsky 28 July 2007 10:59PM

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Comment author: Jack 28 December 2009 11:58:26PM *  -1 points [-]

Uhhh... oxygen exists?

Comment author: DanielLC 29 December 2009 12:40:41AM 1 point [-]

And so does the absence of oxygen, or, as they called it, phlogiston.

Comment author: Nick_Tarleton 29 December 2009 01:01:17AM *  6 points [-]

The absence of oxygen isn't much like a substance whose release is fire:

  • it doesn't have any consistent physical or chemical properties;
  • many things not containing oxygen fail to burn in air, and none burn in vacuum;
  • on the other hand, things do burn under oxidizers other than oxygen;
  • oxidized substances are very poorly modeled by mixtures of the original substance and oxygen;
  • things burned in open air can either gain or lose weight;

etc.

Comment author: DanielLC 31 December 2009 12:41:13AM 1 point [-]

"it doesn't have any consistent physical or chemical properties;"

And oxides do? Or are you referring to pure phlogiston? It's not that big a deal that you can't get pure phlogiston. It's nigh impossible to purify fluorine. I think that under our current understanding of physics, it's totally impossible to isolate a single quark.

It moves because it's attracted to some things more than others. It's still attracted to everything more than itself.

"many things not containing oxygen fail to burn in air"

Hurts both theories equally. Presumably, it's strongly bonded to the phlogiston/it doesn't strongly bond to oxygen.

"...and none burn in vacuum;"

As I said, you can't get pure phlogiston.

"on the other hand, things do burn under oxidizers other than oxygen;"

Hurts both theories equally. The only way to solve it to my knowledge is that there are things that cause fire other than phlogiston/oxygen.

"things burned in open air can either gain or lose weight;"

Hurts both theories equally. Presumably, some of the matter escapes into the air sometimes.

Everything you listed either is only a very minor problem or is exactly as bad for the idea of oxygen.

Comment author: Jack 29 December 2009 05:05:12AM 10 points [-]

You're giving phlogiston qualities no one who held that theory gave it. If you want to call the absence of oxygen phlogiston, okay, but you aren't talking about the same phlogiston everyone else is talking about. Moreover, thinking about fire this way is clumsy and incompatible with the rest of our knowledge about physics and chemistry.

We already had a conception of matter when phlogiston was invented... and phlogiston was understood as a kind of matter. To say the phlogiston is really this other kind of thing, which isn't matter but a particular kind of absence of matter is both unhelpful and a distortion of phlogiston theory. The whole point of the phlogiston theory was that they thought there was a kind of matter responsible for fire! But there isn't matter like that.

Now by defining phlogiston as the absence of oxygen you might be able to model combustion in a narrow set of circumstances-- but you couldn't fit that model with any of your other knowledge about physics and chemistry.

In short neither the original kind nor your kind of phlogiston exist.

Comment author: DanielLC 31 December 2009 12:32:22AM 1 point [-]

It was at one point theorized to have negative mass. If it's matter, and you make everything else weigh more, it works out the same.

I fail to see why you think it can't fit it with other knowledge of physics and chemistry. You can think of electricity as positively charged particles moving around with virtually zero loss of predicting power.

Comment author: Jack 31 December 2009 01:19:21AM 3 points [-]

For example, you can't use phlogiston in any model that also includes oxygen. Nor can you do any work at the molecular or sub-molecular level.

Similarly, thinking of electricity in terms of positively charged particles would be incompatible with atomic theory.