Siphonaptera (poem)

Siphonaptera is a rhyme by the mathematician Augustus De Morgan,^[1] named for the biological order of the flea.

Big fleas have little fleas upon their backs to bite 'em,
And little fleas have lesser fleas, and so, ad infinitum.
And the great fleas, themselves, in turn, have greater fleas to go on;
While these again have greater still, and greater still, and so on.^[2]

The first two lines derive from part of Jonathan Swift's long satirical poem On Poetry: a Rhapsody (1733):

The vermin only teaze and pinch
Their foes superior by an inch.
So, naturalists observe, a flea
Has smaller fleas that on him prey;
And these have smaller still to bite 'em,
And so proceed ad infinitum.
Thus every poet, in his kind,
Is bit by him that comes behind^[3]

Lewis F. Richardson adapted the poem to meteorology, specifically referencing fractal wind patterns:^[4]

Big whorls have little whorls
That feed on their velocity;
And little whorls have lesser whorls
And so on to viscosity.

Gene V. Glass quoted an anonymous adaptation of the poem to educational measurement:^[5]

Big criteria have little criteria,
Upon their backs to bite ‘em;
And little criteria, have littler still,
And so on ad infinitum.

References

See also

• Self-similarity