welcome covers

Your complimentary articles

You’ve read one of your four complimentary articles for this month.

You can read four articles free per month. To have complete access to the thousands of philosophy articles on this site, please


Why alchemists can make gold

Rebecca Bryant on the essence of essentialism.

Essentialism is the doctrine that the objects which we (correctly) group together (such as all trees or all tables), belong together by virtue of some fundamental unchanging nature which they all possess. This fundamental nature may take the form of a set of defining properties which are singly necessary and jointly sufficient for membership in a class. Or, more recently, it has been taken to be some kind of underlying internal structure, which is amenable to scientific discovery. 1

The question I want to ask is, “Do particular objects really possess essences by virtue of which an intrinsically correct classification of all the objects in the world can be produced for once and for all?”

Let’s start off with the easy case of artefacts; things like chairs and tables, with which, I hope, we are all familiar. A mathematician recently commented, “Surely the reason that we call all tables ‘table’ is because they are all tables, Rebecca!” What this shows is that we tend to assume that things labelled with the same term must share something fundamental in common. Is this an essence?

I suggest that it is not an essence, at least not according to the usual philosophical use of that word. Rather, it seems to me that the reason we label all tables ‘table’ is that they are all, or could all be, or were intended by their maker to be used by people as tables. That is, we sit down at them, or we eat our meals at them, or we place our coffee cups on them, or we write essays at them. These are some of the things which might constitute being a table, but this is not some underlying ‘n-ness’ or some set of defining conditions, rather it is the use to which we put these objects and this is something which is socially, not genetically or chemically, determined.

Furthermore, I believe that any object which was used so as to fulfil the function of a table, would correctly be termed ‘table’. Say I had just moved house and my new dining table had not arrived yet, but I refused to succumb to the trend of TV dinners. In this case an upturned packing case, covered with an old curtain, would qualify as a table.

Suppose I have gone camping with some friends. At suppertime we notice a large round tree stump. We decide to sit crosslegged around this and eat our plates of baked beans at it. Again, this would qualify as a table.

It might be that in the above scenarios, the objects in question are not particularly good or stereotypical examples of tables. However, this is just because they do not perfectly fit the conventional or characteristic definition of the term; cross-plank with four legs, used for sitting and eating meals at, for instance. Although they lack some characteristic features, the way in which they are used places them firmly within the scope of the term.

The other problem with the notion of essences, is what happens to them in the case of mishap? Suppose someone takes an axe to a wooden table, which renders it useless for eating at. Is this still a table? Well, it can no longer be used as a table, so I would maintain that it no longer is a table, at least in any interesting (or useful) sense. Perhaps the more cautious among us would say that it was a broken table, which I see as amounting to the same thing. In any case, it is no longer capable of fulfilling the function required of a table and is, at the very least, a table-withreservation. What has happened to the essence? Is it now latent, or has it gone permanently AWOL? Suppose I decide to use the ill-fated table to light my fire. The table is now fuel (that is what I am using it as); has the table essence now been converted to fuel essence? Soon the fuel will be ashes. What has happened now?

To change the example slightly, suppose I decide that the table can be mended. I get out my tool box…. The table is once more like new and in use at mealtimes. Has the temporarily latent essence been restored to full health now? Even more puzzling; I decide that I want to make the old table into a new chair, so out comes the saw. It now seems that the old table essence has been reborn as chair essence.

I find this very confusing. It seems that there is much more to essences than meets the eye. Rather than providing a rigid taxonomy of the world, they appear to be volatile; we can manipulate them at will.

“Fair enough,” I hear you say, “but no one ever really thought that essentialism applied to artefacts. Of course artefacts are defined by social use – that, after all, is what an artefact is – something created by humans for human use.” 2 Well, I did start out by saying that they were the easy case!

So, let’s move on to the really difficult case, the case of so-called natural kinds. Here it is claimed that objects existing in nature fall into certain preordained kinds, by virtue of some sort of underlying structure. As our science progresses and we discover the truth, we will become aware of these kinds together with the structural basis for their division.

The subject-matter most favoured seems to be the chemical elements. These are seen as prime examples of natural kinds which are delimited by their atomic number (the number of protons in the nucleus of the atom). This surely can have nothing to do with socially defined use and, as many a failed alchemist will tell you, gold cannot be made!

I find this kind of approach dubious for a number of reasons. First of all, I don’t doubt that each atom of the element we call gold contains 79 protons in its nucleus – this is a material fact which has been scientifically discovered and the facts cannot be altered. However, I do not agree that by discovering this fact, we have discovered the essence of gold or that this essence makes our chemical taxonomy the one that nature intended.

I want to set the scene here by looking at an argument used by Keith Donnellan in 1983. He was actually trying to make a slightly different point from mine, but his ideas fit my purposes very well. He invites us to imagine a Putnamesque Earth/Twin Earth situation [see box], comprising two cultures with exactly the same language and scientific theory. In particular, they have exactly the same atomic theory. Like us, the Twin Earth people consider that atoms have nuclei containing positively charged protons and neutrally charged neutrons. They call the number of protons in the nucleus of the atom the “atomic number”. They have the concept of an “isotope”. Isotopes of a particular element are individuated by the combined number of protons and neutrons in the nucleus of the atom. This number is known as the “isotope number”. In general, an element will have several different isotopes.

Donnellan asks us to imagine that on Twin Earth, as on Earth, it is usually the case that one of the isotopes of a given element makes up the bulk of that element as it naturally occurs. It so happens that the Twin Earthians do not identify a natural kind term with an element, but rather with the isotope making up the bulk of that element. Thus gold, for them, is a particular isotope with a particular isotope number. The rarer isotopes of the element with atomic number 79, which we take to also be gold, they dismiss as not being real gold. Donnellan extends the picture to water; on Twin Earth, the term ‘water’ is only identified with protium oxide and excludes so-called ‘heavy water’ (deuterium or tritium oxide), which we would consider to also be water as well.

The point I want to extract from Donnellan’s thought experiment is that we can imagine a situation in which some chemical fact other than atomic number is used to divide the chemical world into kinds. There are alternative ways of doing things and just so long as the alternatives are all based on objective fact, there is no question of one being right and the others wrong. For the Twin Earthians, what is fundamental in defining gold or water is possession of a certain isotope number; for us, it is possession of a certain atomic number. What defines a natural kind is not a matter of metaphysical essence, but of how the boundaries are drawn. In fact, it is the boundaries which dictate what will count as definitive and not vice versa.

Our society has merely decided that having atomic number 79 is what should count as the dividing line in our definition of gold. There are other places at which we could have decided to draw the line, but did not. At some stage, the decision was made to take into account atomic number, but to disregard isotope number. Things might have gone a different way; the scientific community, as on Twin Earth, could have decided that what were really important were variations in the number of neutrons, rather than uniformities in the number of protons. The lines along which we draw our natural kind divisions would be differently specified. In effect, we would have different natural kinds. We would still be dealing with objective facts (the combined number of protons and neutrons in the nucleus), but we would be using these facts to divide up the world in a slightly different way. So, it begins to look as though the social world has some influence, even in the apparently rigid domain of natural kinds.

Let’s take things a step further. Imagine a society called UnEssence, which is as scientifically advanced as our own, so that it knows all about atomic numbers, protons, neutrons and things of that ilk. In some cases, the scientists of UnEssence might accept atomic number as defining a particular element, but in the case of gold, things are different. What is really important about gold in their society is its beauty; its colour, the look of it. It has no corresponding economic value; it is not sold for hundreds of pounds in the jewellery shops of UnEssence, it is not present in the vaults of the Bank of UnEssence. Rather, it is regarded more as we might regard a particularly attractive wild flower – as an example of natural beauty.

Now, as it happens, what we call iron pyrites (or “fool’s gold”) looks remarkably similar to what we call ‘real’ gold, even though it has a different chemical structure. Remember that the people of UnEssence are interested in the look of things. As a result they call both gold and iron pyrites by the same name – according to their terminology both are one and the same, both are gold.

What has happened here is that the criteria of interest have shifted. For the people of UnEssence, the most salient fact about UnEssentialist gold is its colour and appearance. This overrides differences in chemical structure and, because there is no economic value involved, there is no need to distinguish between what we call ‘real’ gold and iron pyrites. Again, you are dealing with objective facts, but these facts have been used to divide the world up in a different way. I maintain that this is simply a more extreme version of the atomic number/isotope example given above.

Take another closely related example. We can imagine that in some cases a particular combination of impurities present in the gemstones ruby, sapphire and emerald, produces a distinctive spiral pattern throughout the stones. It is possible to state in very precise scientific terms exactly which impurities must be present in what quantities in order to produce this patterning. It is also possible to describe the exact process which results in this effect. The scientific community might decide that this spiral patterning constitutes a natural kind, irrespective of whether it occurs in a diamond, sapphire, or emerald. This kind is labelled ‘spirellum’. What has happened is that the scientists have taken a product occurring naturally, which they are able to define by means of objective facts involving types and amounts of impurity together with causal origin, and have used these facts to delimit a natural kind. They have chosen to take account of certain facts (spiral pattern, impurity and causal process) and to ignore certain others (surface differences and differences in chemical structure between gemstones). I maintain that this is no different from what scientists in the real world do; it is all a matter of fixing boundaries.

So, what I am suggesting is firstly that essentialism is not true and secondly that our definitions of kinds may be far less constrained than most people tend to believe.

Despite this insight, I have been at pains to emphasise throughout that however we define our kinds, this doesn’t alter the fact that in so-doing we will be relying on the specification of certain objective facts. There may be many alternative ways of carving nature up into kinds; there may not be one ultimate way intended by nature, but this does not involve loss of objectivity, or even realism, for that matter.

At some point a decision has been made as to how the world should be divided; a basis for division has been chosen. This involves recognising the saliency of certain objective facts and ignoring certain others. Once the basis has been settled upon, you have a social component in your categorisation of kinds. This is a criterion which is accepted by society and used as a bench mark for division.

What essentialists fail to recognise is that categorisation is a holistic and socially motivated affair. Essentialism concerns itself only with metaphysics, with the way the world is. It pays no attention to means by which human beings may contribute to the way the world is. Kinds are believed to pre-date man and to be based simply on possession of some fundamental nature. As I have already said, the divisions that we make are only one possible strategy among many. It needs to be acknowledged that man has a hand in shaping the categories of the world and so these categories do not rest simply on possession of properties, but on a whole theory of action, on a strategy. The principles on which our divisions rest incorporate a whole host of other things; choices, decisions, methodology, theories about what constitutes good scientific practice, man’s development through history, how man interacts with his environment and so on. Essentialism provides an easy and tidy way out, but it is not the correct way out. Categories incorporate much more than the way the world is. We need to consider why we see the world as we do and how this is a product of our thought processes acting upon the world.

I believe that the term ‘natural kinds’ is misleading. It suggests that the categories of which we speak are somehow predetermined by nature and I hope I have shed doubt on this. We need to recognise that man is as much a part of the environment as anything else and that he thus plays a part in how that environment looks. I fear that essentialist accounts tend to draw an unerring line between the world as it is in itself and man’s perception of it, which, with a bit of luck and a lot of scientific skill, will eventually come to portray that world in its true light, replete with natural categories. This is a false picture. We chose certain categories, but we could have chosen others. As long as alternative categories are based on objective facts, on ways the world is, then they will be equally natural. The true picture is of the world as a whole host of potentialities, with people actualising only some of those potentialities.

To turn back, perhaps rather belatedly, to the title of this article, it seems that there is a way in which we can ‘make’ gold. Obviously, this doesn’t involve physical manipulation of base metals, but what it does involve is the ability to draw boundaries where we choose to draw them. What gold is will depend on how we decide to define it. If we decide that all elements with atomic number 79 are gold, then ‘gold’ will be what we take it to be. However, if we decide that gold comprises elements with atomic number 79 and iron pyrites, then the meaning of ‘gold’ will be different. We will, in effect, have succeeded in making gold.3


Donnellan, K.S. (1983). ‘Kripke and Putnam on Natural Kind Terms’ in Knowledge and Mind ed. by C. Ginet and S. Shoemaker. Oxford University Press.
Putnam, H. (1973). ‘Meaning and Reference’. Journal of Philosophy, pp.699-711.
Putnam, H. (1975). ‘The Meaning of ‘Meaning’’ in Philosophical Papers: Volume 2. Mind, Language and Reality ed. by H. Putnam. Cambridge University Press.


1 Especially Hilary Putnam, 1973, 1975.
2 Some of you might even say that the use to which an artefact is put constitutes its essence. I find this move extremely hard to swallow and quite contrary to what I understand to be the spirit of essentialism.
3 Now you understand why so many failed alchemists decide to become philosophers!

© R. Bryant 1996

Rebecca Bryant is a PhD student in the Philosophy Department at Edinburgh University

The Twin Earth Thought Experiment

This is a thought-experiment invented by the American philosopher Hilary Putnam in 1975. He asked us to imagine a planet called Twin Earth which is identical to our own Earth in nearly all respects but with one subtle difference. On Twin Earth all the rivers, lakes and so on are full of a substance which looks, tastes and smells just like water, but which actually has a different chemical composition from water on Earth (XYZ rather than H2O). The inhabitants of Twin Earth are very much like us, but the question Putnam asks is “What do they mean when they talk about water?” Do they mean XYZ? If so then meaning isn’t just a question of what’s going on in your head, because the things going on in the Twin Earthers heads are just like the things that go on in your head when you say “That is water there”, even though they apparently mean something different. Therefore Putnam says that meaning must be (at least partly) to do with what is out there in the world. The whole Twin Earth scenario has become very popular with philosophers who want to test out their ideas about meaning and language.

This site uses cookies to recognize users and allow us to analyse site usage. By continuing to browse the site with cookies enabled in your browser, you consent to the use of cookies in accordance with our privacy policy. X