I briefly mentioned an overhead transparency I nicknamed OHT1 in an earlier post. I also mentioned how, although there was no official OHT2, there was an image I would have used. Both of these I shall be dwelling on in greater detail in future. Here, I point out a third transparency that was deliberately absent. Thus, I call it the ‘Non-OHT3’. There is, of course, no accompanying image. This absent transparency represents how the idea of homeostasis (sometimes spelt homoeostasis) was deliberately missing from my teaching.
That may seem strange. High school pupils studying biology learn about homeostasis. As described there, it is something essential for life. It is a vital characteristic possessed by organisms such as ourselves. Definitions of homeostasis describe the body maintaining a stable internal state despite external changes. The word ‘balance’ is often applied - I suggest somewhat indiscriminately. It remains a popular notion even in higher education. I know of physiology books written based on the principle of homeostasis. I contend that that is because it is a notion expounded uncritically. It makes sense until analysed carefully.
I deliberately avoided discussing homeostasis except to urge caution when reading about it. It gives the impression of a somewhat passive body. Instead, the body is highly active. Those who have looked at homeostasis carefully have raised doubts about its voracity. Accordingly, they have proposed alternative dynamic alternatives.
I shall return to these in due course.
