True and False Cold or Heat hán rè zhēn jiǎ · 寒热真假

A classical caution about appearances: a picture that looks like heat can in fact be cold at root, and the reverse also occurs. The tradition uses this to argue that the most obvious sign is not always the decisive one.

Criteria proposed in the classical literature include whether the person wants to be covered or uncovered, whether they want cold drinks, the character of the pulse, and how the tongue looks. None of these is decisive alone.

This is the clearest example of why the library does not do diagnosis. What looks like one thing and is another is exactly the situation where self-assessment is most likely to be wrong. If someone is very unwell, the answer is medical care, not pattern analysis.