I begin with Chapter 7 from the 6th standard NCERT textbook for Science titled, ‘Getting to Know Plants’. It is in the 6th standard that science is first introduced as a separate subject, although the subject of Environmental Science is taught from 3rd to 5th standard. Chapter 7 is the first chapter in it dedicated to basic concepts under botany.
The introductory section of the chapter consists of observing the plants in the surroundings of the reader, and an invitation to learn about the different parts of any plant- the stem, branch, root, leaf, flower and fruit. The claim that any plant will have these parts seems to be a bold assertion. I would like to examine if it can be considered an established fact.
One way to examine it would be to ask how this fact (if it is one), came to be established. This requires us to be familiar with who first proposed this idea, what others added onto or modified about them, and what arguments the present scientific community give in favour of or against the claim. Another way would be to verify this claim for ourselves through observations. It is commonplace to hear that the process by which such claims are arrived at and assessed by science, ‘the scientific method’, is to make a large number of observations, in varied contexts, and arrive at a general conclusion that applies to them all. According to this view, this is how the ‘laws of nature’ which apply to all physical entities are discovered, from a limited number of observations of them. This is called the ‘inductivist’ idea of the scientific method.
To employ inductivism in the case of this claim, we would have to know what a ‘plant’ is, and what is meant by a ‘stem, branch, root, leaf, flower and fruit’. Then, we would have to observe every ‘plant’ there is and see if it has these ‘parts’. But a crucial question to consider before we make this attempt is that of whether we have a means of specifying what a plant is independent of these parts. To elaborate, if we were to try to make observations of an enormous number of plants, we would have to know what we are looking for. How would we identify a plant if we were to see it? If our criteria for calling something a plant are themselves the presence of a stem, branches, roots, leaves, flowers, and fruits, we are not really verifying the claim in the ‘empirical’ sense.
It is akin to claims like ‘All Indians have Indian citizenship’ which are true by definition. The word ‘Indian’ itself means someone who has ‘Indian citizenship’. Therefore, it is equivalent to the claim that ‘All Indians are Indians’, or ‘All who have Indian citizenship have Indian citizenship’. We do not rely on any observation to confirm such statements which are true by definition. It is in this sense that they may not be considered ‘empirical’ statements. We may very well make observations and try to answer it, but we will only consider things with stem, root etcetera to be plants. More importantly, what does not have these parts, we would never consider plants in the first place. Let us first check if this is the case with the claim that all plants have the parts mentioned before.
One way to do this is to check the NCERT textbooks of lower
classes for a definition. I could not find any definition of plants there.
Another way to check this would be to consult a book, or someone well versed in
the subject or, the internet. Consider the definition of a plant in Britannica-
“plant, (kingdom Plantae), any multicellular eukaryotic life-form characterized by (1) photosynthetic nutrition (a characteristic possessed by all plants except some parasitic plants and underground orchids), in which chemical energy is produced from water, minerals, and carbon dioxide with the aid of pigments and the radiant energy of the Sun, (2) essentially unlimited growth at localized regions, (3) cells that contain cellulose in their walls and are therefore to some extent rigid, (4) the absence of organs of locomotion, resulting in a more or less stationary existence, (5) the absence of nervous systems, and (6) life histories that show an alteration of haploid and diploid generations, with the dominance of one over the other being taxonomically significant.”
Merely trying to understand every term at depth would itself
require enormous study, given that we wish to not make a straw-man of science
but engage with it seriously. Let us pick up one term, ‘eukaryotic’. Its
definition in Britannica is-
“Eukaryote, any cell or organism that possesses a clearly defined nucleus.”
Now, the definition for ‘cell’ which the above definition uses-
“cell, in biology, the basic membrane-bound unit that contains the fundamental molecules of life and of which all living things are composed.”
It should be evident by now how difficult it is to explicitly state what a plant is, even though we are only trying to analyze just one word from every subsequent definition. Every word we use to define a plant will all be words whose meanings are to be ascertained. The rate at which the words in need of clarifying appear is much larger than the rate at which we could clarify them. Moreover, the very act of clarifying produces more words requiring clarification!
But this is true for just about any word. The reader will have read multiple words in this document and could very fairly ask for what every single one of them means to be stated explicitly. It would be a nightmare for me to even attempt that! Nevertheless, the reader will agree that most of it, they are able to comprehend. Similarly, we are able to identify a plant despite not being able to state explicitly what it is.
There is another argument that can be made. The above problem arises only when we restrict ourselves to clarifying words through other words. What if, when asked what a plant is, we point to a real plant? And then, many many more? How about if we were to give photographs of plants? This may very well be the approach with which the introductory section of the chapter was crafted. The invitation is to go out and see real plants and see if they all have these parts. In fact, the section ends with a sketch of a plant (Fig 1.2 in the chapter) and a request to label the different parts of the plant in it and colour it.
Even in this case, some questions arise. There is a large variety amongst real plants. There are differences between even individual plants within the same species. Yet, there are some similarities between them too. Specifying these differences and similarities in words may not prove easy, but if we were asked to just identify whether something is a plant or not, we would very easily do it (in most cases). This can be observed to be in play in recognising faces as well. Every face differs in some ways from another and the same face can look different depending on head accessories, make up, the extent of facial hair, lighting etc. yet we are able to identify faces we ‘know’. Even the currently prevalent way to tell humans apart from machines as a security measure of various websites, is to give them the task of identifying something (say, a road sign) amongst different pictures, some of which have that something (road signs) and some that don’t. This ability to recognise patterns which escapes the spoken and written word is what Michael Polanyi calls a ‘tacit knowing’. He argues that it is at play in innumerable activities we perform, and is involved in many aspects of the scientific practice.
Let us revisit the question we started with. Can a plant be defined independently of the parts we mentioned? Yes. But we could always ask the same question of that definition. Namely, we could ask if it could be defined independently of the terms in the new definition. To define, in itself, involves self-reference, it appears. But does that mean that there is no such thing as an ‘empirical’ claim? For now, let us proceed further and see whether this problem emerges elsewhere (which I suspect it will).
There is yet another angle to this investigation. It is possible that when the textbook invites the reader to learn about the parts which any plant has, it may very well be an attempt to define. It may not be intended to be a claim at all, whether empirical or non-empirical. To define a plant as something which has a stem, branches, leaves, roots, and flowers is a very simple and effective definition. This should be clear when it is contrasted against the definition of a plant in Britannica. This simple definition of a plant is adequate to carry out further activities in the chapter. So let us proceed with it.
The introduction also mentioned that by observing these different parts of plants we can tell different kinds of plants apart. The first activity is to carry out this very task. It is explained that most plants can be classified into three categories- herbs, shrubs, and trees. Herbs are said to possess green and tender stems, have few branches, and are short. Shrubs have hard, but not thick stems, their branches start emerging from the stem even very close to the ground. Their height is about as much as a child in the 6th standard. Trees are tall, have thick and hard stems, and have branches mostly from the taller parts of the stem.
The following photographs of one plant of each category is presented in the textbook –
Further into the chapter, climbers, creepers, and weeds are also introduced as kinds of plants which do not fall under these categories. I visited a botanical garden called Lalbagh, nearby, and observed various plants there. The classification system seemed to cover most of the plants I observed. A few however, seemed to not fall into any of these categories in a straightforward way. I am sharing their pictures below-
This plant appears to be a tree, except in terms of height. Perhaps it is the result of some human intervention and is not how it naturally grows.
This appears to be a tree, except for how its leaves are. The leaves not only differ from other trees, but also do not resemble the leaves associated with any other plant variety present in the botanical garden.
This article is part of a series attempting a philosophical analysis of biology as encountered in NCERT textbooks. To read the concept note for the series, click on the link below-https://www.barefootphilosophers.com/concept-note-for-series/