My opinion about the cold/no-heat question is somewhat related to my dislike of so-called philosophical languages (like Loglan). In formulating concepts one has two choices: how human beings sense things, and how we know that nature works. My choice would be for the humanocentric approach. If people feel cold as a real feeling, not simply the absence of heat (and we certainly do), then I would suggest using "cold" and not "no-heat." I could add the caveat that it might be worthwhile looking at other languages than English. If it turns out that a lot of natural languages use "non-hot" to mean "cold", then I could see using it. But every language that I've studied has a separate word for "cold".

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