B: The other day scientists were able to lower the temperature of some molecules a few hundredths of a degree below absolute zero. That's amazing!
A: That's not amazing, that's impossible! You can't have negative heat! There's no such thing!
B: It's not impossible. You just don't understand what temperature really is.
A: Everyone knows what temperature is.
B: Everyone thinks they know what temperature is, but they don't. Not really.
B: Everyone thinks that temperature is a measurement of heat, but it isn't. When we measure how hot or cold something is, we're actually measuring an expression of temperature, rather than temperature itself.
B: At absolute zero, the expression we measure to determine temperature is no longer reliable, and scientist have to use different methods to measure it, but even without the effect, temperature still exists.
A: So temperature isn't really temperature.
B: No temperature is still temperature. It just isn't heat.
A: ... because sometimes it's cold.
B: Well, no... cold is heat. It's just less heat than hot.
A: Why do I suddenly want to punch you in the face?
It should be noted that the title of this comic is "A Theatre Major Tries To Explain Science." This is what I got from trying to read an explanation of how it's possible to measure temperatures below 0 Kelvin. I'm fairly certain this attempt is wrong. I'm also fairly certain the experience directly informed A's response at the end of this comic: after reading the explanation, I really did want to punch someone in the face.