Skip to main content

What is an element?

I know it's Friday, but pay attention, we're going to do a bit of philosophy. I'm dredging this up from memory, so feel free to correct me if I've got the details wrong, but the essence is there, which I think will prove significant.

I suspect it was Plato who suggested that there are types and shadows (I just love the medieval terminology) - types or archetypes are the 'real thing', the ultimate essence of the concept, while shadows are the physical world entities corresponding to those types. So, for instance you might have the type of 'cat' which embodies all catness, while the moggy down the street is just a shadow, embodying parts of the ultimate concept.

I was interested to see a very similar idea emerging from a discussion of the philosophy of chemistry (no, really). Eric Scerri of the University of California, Los Angeles (general nice guy and author of an interesting book on the periodic table) suggested we need a similar approach to the elements. Sodium, for instance. Yes it's a grey-silver metal that does exciting things when you drop it in water. But 'It is more proper, perhaps, to think of elemental sodium as that thing that gives properties not just to the metal but also to NaCl and other compounds. Sodium may be best described as that abstract thing that you point to on the periodic table, defined only by its atomic number...'

In this picture, the abstract thing on the periodic table is surely a type, with the lump of metal, or the component of salt, a shadow.

Whatever, I think it's fascinating - and for those who think chemistry is all test tubes and fume cupboards, a bit of an eye-opener. Click here to read more about a recent discussion on the philosophy of chemistry.

Comments

  1. Interesting way of reclassifying chemical knowledge - but still think the conventional thinking on the periodic table is more practically useful.

    ReplyDelete
  2. close -Plato posited that all things in the material world are like shadows cast on a cave wall to people who never leave the cave (us). These shapows are to the real world outside the cave as real objects are to the 'ideal' forms of things.

    ReplyDelete
  3. Clare - I don't think the idea is to dispose of conventional thinking, but to supplement it.

    Dave - that's the fellow. I think the 'types and shadows' version is a medieval development on Plato's cave.

    This comes through, for example, in the medieval hymn 'Now, my tongue, the mystery telling' which has the lines: 'types and shadows have their ending/for the newer rite is here.'

    ReplyDelete

Post a Comment

Popular posts from this blog

Is 5x3 the same as 3x5?

The Internet has gone mildly bonkers over a child in America who was marked down in a test because when asked to work out 5x3 by repeated addition he/she used 5+5+5 instead of 3+3+3+3+3. Those who support the teacher say that 5x3 means 'five lots of 3' where the complainants say that 'times' is commutative (reversible) so the distinction is meaningless as 5x3 and 3x5 are indistinguishable. It's certainly true that not all mathematical operations are commutative. I think we are all comfortable that 5-3 is not the same as 3-5.  However. This not true of multiplication (of numbers). And so if there is to be any distinction, it has to be in the use of English to interpret the 'x' sign. Unfortunately, even here there is no logical way of coming up with a definitive answer. I suspect most primary school teachers would expands 'times' as 'lots of' as mentioned above. So we get 5 x 3 as '5 lots of 3'. Unfortunately that only wor

Why I hate opera

If I'm honest, the title of this post is an exaggeration to make a point. I don't really hate opera. There are a couple of operas - notably Monteverdi's Incoranazione di Poppea and Purcell's Dido & Aeneas - that I quite like. But what I do find truly sickening is the reverence with which opera is treated, as if it were some particularly great art form. Nowhere was this more obvious than in ITV's recent gut-wrenchingly awful series Pop Star to Opera Star , where the likes of Alan Tichmarsh treated the real opera singers as if they were fragile pieces on Antiques Roadshow, and the music as if it were a gift of the gods. In my opinion - and I know not everyone agrees - opera is: Mediocre music Melodramatic plots Amateurishly hammy acting A forced and unpleasant singing style Ridiculously over-supported by public funds I won't even bother to go into any detail on the plots and the acting - this is just self-evident. But the other aspects need some ex

Which idiot came up with percentage-based gradient signs

Rant warning: the contents of this post could sound like something produced by UKIP. I wish to make it clear that I do not in any way support or endorse that political party. In fact it gives me the creeps. Once upon a time, the signs for a steep hill on British roads displayed the gradient in a simple, easy-to-understand form. If the hill went up, say, one yard for every three yards forward it said '1 in 3'. Then some bureaucrat came along and decided that it would be a good idea to state the slope as a percentage. So now the sign for (say) a 1 in 10 slope says 10% (I think). That 'I think' is because the percentage-based slope is so unnatural. There are two ways we conventionally measure slopes. Either on X/Y coordiates (as in 1 in 4) or using degrees - say at a 15° angle. We don't measure them in percentages. It's easy to visualize a 1 in 3 slope, or a 30 degree angle. Much less obvious what a 33.333 recurring percent slope is. And what's a 100% slope