According to Pythagoras by Michael Longley (Collected Poems, Cape Poetry)

When in good time corpses go off and ooze in the heat

Creepy-crawlies breed in them. Bury your prize bull

(A well-known experiment) - and from the putrid guts

Sward flower-crazy bees, industrious country-types

Working hard, as did their host, with harvest in mind.

An interred war-horse produces hornets. Remove

A shore-crab's hollow claw, lay it to rest: the result

Is a scorpion charging with its tail bent like a hook.

Worms cosy in cocoons of white thread grow into

Butterflies, souls of the dead. Any farmer knows that.

Germs in mud generate green frogs: legless at first

They soon sprout swimming and jumping equipment.

A she-bear's cub is a lump of meat whose stumpy

Non-legs she licks into shape in her own image.

The honey-bees' larvae hatched in those waxy hexagons

Only get feet and wings later on. That's obvious.

Think of peacocks, eagles, doves, the bird-family

As a whole, all starting inside eggs: hard to believe.

There's a theory that in the grave the backbone rots

Away and the spinal cord turns into a snake.

The fundamental interconnectedness of all things

Is incredible enough, but did you know that

Hyenas change sex? The female mounted by the male

Just minutes before, becomes a male herself. Then

There's the chameleon that feeds off wind and air

And takes the colour of whatever it's standing on.

Air transforms lynxes' urine into stones and hardens

Coral, that softly swaying underwater plant.

I could go on and on with these scientific facts.

If it wasn't so late I'd tell you a whole lot more.

Pythagoras was a Greek philosopher and mathematician, alive in 530 BC. As well as discovering that the square on the hypotenuse was equal to the sum of the squares on the other two sides of a right-angled triangle, he believed in reincarnation - that a man's soul could come back as a squirrel or a dog, and be free of fleshy constraints only if the individual led a truly pure life. As I understand it, it was this purity that the Pythagoreans sought in order to escape the “wheel of birth”. Their early origins appear to have been in religion rather than philosophy.

The “interconnectedness of all things” is explored through the cycle of life and death: if we bury a dead prize bull (or would any old cow do?) then we might harvest bees. And will a scorpion grow from the “shore-crab's hollow claw”? Or is it that the shape of one resembles the shape of the other, and so the two ideas are met?

We are told that farmers - with their inherent knowledge of life and death - know that butterflies grow from “worms cosy in cocoons of white thread”, and that they are the souls of the dead. Even though this may not be true, it is a form of respect for the dead to think of them so beautifully coloured and glorious in their new, short and glamorous lives.

The germs in mud that produce green frogs may actually be the frogspawn, but the image that sticks in my mind is the bear cub's mother who “licks into shape in her own image” the bundle of fluff to which she has given birth. It conjures a vivid picture of her huge tongue almost lifting the tiny cub off its rudimentary paws as she cleans it. This is followed by the evolution of honey-bees from larvae and the observation of the improbable origin of birds.

If birds come from something as bizarre as a smooth ovoid container with no exit or entry, then it's not too far of a stretch to imagine that the backbone of a corpse becomes a snake. The idea connects the flexible aspects of a spine that has no human attached with a bendy snake that has no legs attached. If we buried a corpse, left it to rot, then dug it up to find nothing there but a snake, then, in a less enlightened world, we might conclude that “spinal cord = snake”.

We are made to think about what is real and what is not: if cadavers really do play host to the creepy-crawlies that eat rotting flesh, does the female hyena really become male just after being mounted? If so, how? Genitalia are difficult to change from female to male (or vice versa) without a scalpel and surgeon. Chameleons do change colour without medical intervention, but does lynxes' urine really become stones when exposed to the air? Perhaps they just peed on rocks ... coral, however, does become hard in the air because it dies and dries out.

The Pythagoras of the poem calls these “scientific facts” but they are a result of his observation of the cycle of life combined with superstition and theory, and he is an old man loving an audience and in wonder at the world.

frieda.hughes@thetimes.co.uk

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