Lewis Carroll on how watching the clock can help you drift off

In preparing the second edition of my book Pillow Problems Thought Out During Sleepless Nights, I replaced the words ‘sleepless nights’ by ‘wakeful hours’. The change was made in order to allay the anxiety of kind friends, who had written to me to express their sympathy in my broken-down state of health, believing that I am a sufferer from chronic ‘insomnia’, and that it is as a remedy for that exhausting malady that I have recommended mathematical calculation.

The original title was not, I fear, wisely chosen; and it certainly was liable to suggest a meaning I did not intend to convey, viz. that my ‘nights’ are very often wholly ‘sleepless’. This is by no means the case: I have never suffered from ‘insomnia’: and the over-wakeful hours, that I have had to spend at night, have often been simply the result of the over-sleepy hours I have spent during the preceding evening! Nor is it as a remedy for wakefulness that I have suggested mathematical calculation; but as a remedy for the harassing thoughts that are apt to invade a wholly-unoccupied mind.

To state the matter logically, the dilemma which my friends suppose me to be in has, for its two horns, the endurance of a sleepless night, and the adoption of some recipe for inducing sleep. Now, so far as my experience goes, no such recipe has any effect, unless when you are sleepy, and mathematical calculations would be more likely to delay, than to hasten, the advent of sleep.

The real dilemma, which I have had to face, is this: given that the brain is in so wakeful a condition that do what I will, I am certain to remain awake for the next hour or so, I must choose between two courses, viz. either to submit to the fruitless self-torture of going through some worrying topic, over and over again, or else to dictate to myself some topic sufficiently absorbing to keep the worry at bay. A mathematical problem is, for me, such a topic; and is a benefit, even if it lengthens the wakeful period a little. I believe that an hour of calculation is much better for me than half-an-hour of worry.

Even when it is a matter of the most elementary calculation, the process of arriving at a solution may involve a diverting dialogue, viz. the problem of ‘The Two Clocks’:

Which is better, a clock that is right only once a year, or a clock that is right twice every day?

‘The latter,’ you reply, ‘unquestionably.’ Very good, now attend.

I have two clocks: one doesn’t go at all, and the other loses a minute a day: which would you prefer? ‘The losing one,’ you answer, ‘without a doubt.’ Now observe: the one which loses a minute a day has to lose twelve hours, or seven hundred and twenty minutes before it is right again, consequently it is only right once in two years, whereas the other is evidently right as often as the time it points to comes round, which happens twice a day. You see that the clock is right at eight o’clock? Consequently, when eight o’clock comes round your clock is right.

‘Yes, I see that,’ you reply.

Very good, then you’ve contradicted yourself twice: now get out of the difficulty as best you can, and don’t contradict yourself again if you can help it.

You might go on to ask, ‘How am I to know when eight o’clock does come? My clock will not tell me.’ Be patient: you know that when eight o’clock comes your clock is right, very good; then your rule is this: keep your eye fixed on your clock, and the very moment it is right it will be eight o’clock. ‘But—,’ you say. There, that’ll do; the more you argue the farther you get from the point, so it will be as well to stop.

This is an extract from Lewis Carroll’s Guide for Insomniacs, recently published by Notting Hill Editions (£12.99), with an introduction from Gyles Brandreth. Buy a copy here.

Or buy a copy from Blackwell’s here.

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