This post is the second in a series about the use of scientific terminology in the vernacular. This is a topic that I’ve always found fascinating, mainly because it really clarifies how laypeople understand science.

In chemistry and physics, a liquid’s boiling point is the highest temperature at which it will remain liquid. Increase the temperature even slightly and it will change state and become a gas.

According to answers.com, the term “boiling point” has been used informally since the second half of the 1700s to mean a climax, and has come to mean a turning point or point at which one loses one’s temper.

I think this metaphor, although perhaps tired from over three centuries of use, is an excellent one. So often, anger simmers a little before exploding violently, bursting out like the bubbles of air escaping from boiling water. It is also apt as a metaphor for a climax, where a situation may change in the same way as a chemical changes state: both gradually (the temperature increases slowly) and suddenly (the boiling point is a discrete temperature).

This one definitely gets my presumptuous tick of approval.