Zero Population Growth
It was an undergraduate software training course. For hands-on practice, the teacher used demographic data (which was the natural choice). In the course of lectures, he/she (he he, playing safe) naturally had to briefly discuss demographic matters of population growth, fertility, mortality, and all such basic demographic concepts.
In one of his/her lessons, the teacher touched on how – at replacement level when the death rate and the birth rate are equal (migration is obviously not factored in) – there is Zero Population Growth. That is to say, the population will not ‘grow’ and will remain at a certain level through time.
One of the students did not get the explanation and thought that Zero Population Growth meant no new births (he/she obviously did not think it through for if no babies are to be born yet the population must remain stable, it means people would have to be immortal). In any case, this student felt bad for pre-school teachers and said:
Oh, that’s sad. If the population growth is zero, no more babies will be born and pre-school teachers will no longer have anyone to teach. Pre-school teachers will be out of a job!
The student obviously missed the crucial concept… but that’s fine. He/she would learn with the teacher to guide him/her, right?
Unfortunately, this was not the case for in the next instant, the teacher – face sad and tone gloomy – responded.
*Disclaimer: I just heard this through the grapevine when I was still an undergrad student so I can’t vouch for the veracity of this tale. This may be just one of those ‘urban legends’.