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Every time this is posted I want to rebut the water boiling portion. It's finally time.

The author gets the details of boiling water wrong. He commits a fairly common error: using his experience of a practical and common phenomena to make/guess a technical definition. The technical definition of boiling water is simply the temperature beyond which liquid water will not go (let's ignore super heating- too much detail!). The rest of the exposition is unnecessary and wrong given the true definition (although could probably be reworked from a cooking perspective)




> The technical definition of boiling water

is just the start. He starts with "water boils at 100 °C, right?" which I expect you'd agree with.

He then _continues_ to work out that, despite the simple definition, the everyday-life _experience_ of boiling water is nowhere near as simple. Why is it not so simple? Because, details.

Which is the point of the whole essay.

> gets the details of boiling water wrong

Can you give an example of a detail he got wrong?

> The rest of the exposition is unnecessary and wrong given the true definition

His _goal_ is to explore the details of the everyday-life experience of "boiling water" in the everyday sense of "boiling" and show how it's more complicated than what the simple (technical) definition would lead you to believe.

Part of the trouble is that the word "boiling" means two distinct but related things:

1. Heating liquid so much that all of it transitions to gas (your technical definition, restated to be a verb form -- "boiling water", a gerund phrase, cannot be a temperature, as you proposed to define it)

2. Heating liquid so that _some_ of it is transitioning to gas, while the rest of the liquid can be used for cooking

The second sense is what people actually mean when they say "I'm going to boil some water" or "Is the water boiling yet?"


If the discussion was about boiling pasta water I'd be on board (e.g. a discussion of the every day). But it's wearing the clothing of science and so falls flat (for me). None of the details turn out to matter for the real technical definition. Amusingly the one detail that does matter- air pressure and by proxy elevation- is omitted.


That's fair to point out. However, I don't think it detracts from the point: the definition is in some sense a detail, because there is a connection between "bubbles forming" and "the temperature water will not rise beyond", but it's subtle and assuming that one equals the other leads to error. The very reason we have that definition is that it's more precise, because in the real world there's details that escape narrow definitions as seen in school or in the kitchen.

As an aside: I love the bubbling patterns of water as it heats, and it's actually a useful skill in the world of tea-making (especially in the gongfu tradition) to estimate the temperature of water based on the amount and size of bubbles. Nowadays I use a temperature-controlled kettle, but in the past I would get by with a clear borosilicate glass kettle and paying attention to the details, which is fun and rewarding in itself—if far less precise.


The way I read it, that’s why you’re supposed to imagine it’s the 1800s. All you have is the simple-sounding concept of “boiling”, and you’re trying to codify it by finding the temperature beyond which water will not go. At which point you start really paying attention and find the phenomenon is way more complex than your initial model of “water is either boiling or it isn’t”.


But it rather isn't. The temperature keeps going up as you add more fire. And then it stops going up even if you add more fire. That point is the temperature of interest and was from the very start. It isn't hard to find. It isn't hard to understand. It's just a bad example for this essay




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