Why do you call a vicious cycle “positive feedback” when there is nothing good about it?
Feedback is a term that is used in common English and also in science and engineering, but with somewhat different meanings. In everyday English, positive feedback might mean, for instance, a good performance review.
But as used in science and engineering, the positive in “positive feedback” has nothing to do with good or bad. It is positive in the mathematical sense of the direction toward larger numbers. Whether something increasing is good or bad depends on what it is. For instance, an increase in the rabbit population of Australia, where rabbits have no predators, is usually considered a bad thing. An increase in your bank balance due to compound interest is usually considered a good thing. Both are the result of positive feedback.
There is a more common example where “positive” does not mean anything good: medical tests. If you test positive for a disease it means you have the disease.
Are there other words that have different meanings in science from their meanings in everyday English?
Yes. Not just science, but almost every occupation has its own specialized vocabulary. Sometimes the words are taken from common English and given more specialized meanings. Sometimes words that have a technical meaning are adopted into common English, but usually not with exactly the same meaning. Two words that come to mind are “quantum” and “exponential”. In their technical meanings, neither one means “large”.
Another example, one that often leads to misunderstandings, is “theory”. We have all heard people say, “It’s just a theory”. In that common English usage, people mean it is a proposed explanation of something that seems to explain at least part of the phenomenon, but needs to be thoroughly tested before we can say it is the true explanation.
In science, such a proposal is called a hypothesis. Only after a hypothesis has been subjected to every possible test and alternative hypotheses to explain the same thing have been similarly tested, do scientists call the hypothesis that could not be disproved a theory. For this reason, a theory in science holds a high place in our understanding, and it is never used with the word “just”.
Why do you use technical terms like positive feedback if this podcast is intended for non-scientists?
I sometimes include the technical terms to establish my bona fides to any scientists or engineers who may be listening. It is important to my credibility that any technical types who hear the podcast believe I know what I’m talking about. I try to clarify the technical meaning of any term I use. If I fail to make something clear, please ask me about it.
If you have questions, please send me an email.