An analogy based on a science concept
Keith S. Taber
(Image by OpenClipart-Vectors from Pixabay)
Analogies, metaphors and similes are used in communication to help make the unfamiliar familiar by suggesting that some novel idea or phenomena being introduced is in some ways like something the reader/listener is already familiar with. Analogies, metaphors and similes are commonly used in science teaching, and also in science writing and journalism.
An analogy maps out similarities in structure between two phenomena or concepts. This example, from a radio programme, compared the COVID pandemic with photosynthesis.
Photosynthesis and the pandemic
Professor Will Davies of Goldsmiths, University of London suggested that:
"So, what we were particularly aiming to do, was to understand the collision between a range of different political economic factors of a pre-2020 world, and how they were sort of reassembled and deployed to cope with something which was without question unprecedented.
We used this metaphor of photosynthesis because if you think about photosynthesis in relation to plants, the sun both lights things up but at the same time it feeds them and helps them to grow, and I think one of the things the pandemic has done for social scientists is to serve both as a kind of illumination of things that previously maybe critical political economists and heterodox scholars were pointing to but now became very visible to the mainstream media and to mainstream politics. But at the same time it also accentuated and deepened some of those tendencies such as our reliance on various digital platforms, certain gender dynamics of work in the household, these sort of things that became acute and undeniable and potentially politicised over the course of 20230, 2021."
Prof. Will Davies, talking on 'Thinking Allowed' 1
A scientific idea used as analogue
Prof. Davies refers to using "this metaphor of photosynthesis". However he goes on to suggest how the two things he is comparing are structurally similar – the pandemic has shone a light on social issues at the same time as providing the conditions for them to become more extreme, akin to how light both illuminates plants and changes them. A metaphor is an implicit comparison where the reader/listener is left to interpret the comparison, but a metaphor or simile that is explicitly developed to explain the comparison can become an analogy.
Often science concepts are introduced by analogy to more familiar everyday ideas, objects or events. Here, however, a scientific concept, photosynthesis is used as the analogue – the source used to explain something novel. Prof. Davies assumes listeners will be familiar enough with this science concept for it to helpful in introducing his research.
Mischaracterising photosynthesis?
A science teacher might not like the notion that the sun feeds plants – indeed if a student suggested this in a science class it would likely be judged as an alternative conception. In photosynthesis, carbon dioxide (from the atmosphere) and water (usually absorbed from the soil) provide the starting materials, and the glucose that is produced (along with oxygen) enables other processes – such as growth which relies on other substances also being absorbed from the soil. (So-called 'plant foods', which would be better characterised as plant nutritional supplements, contain sources of elements such as nitrogen, phosphorus and potassium). Light is necessary for photosynthesis, but the sunlight is not best considered 'food'.
One might also argue that Prof. Davies has misidentified the source for his analogy, and perhaps he should rather have suggested sunlight as the source metaphor for his comparison as sunlight both illuminates plants and enables them to grow. Photosynthesis takes place inside chloroplasts within a plant's tissues, and does not illuminate the plant. However, Prof. Davies' expertise is in political economy, not natural science, and it was good to see a social scientist looking to use a scientific idea to explain his research.
