Pyramids (Discworld 7)

The Sphinx cleared its throat with a noise like an empty lorry reversing in a quarry.

'What goes on four legs in the morning, two legs at noon, and three legs in the evening?' said the Sphinx smugly.

Teppic considered this.

'That's a tough one,' he said, eventually.

'The toughest,' said the Sphinx.

'Um.'

'You'll never get it.'

'Ah,' said Teppic.

'Could you take your clothes off while you're thinking? The threads play merry hell with my teeth.'

'There isn't some kind of animal that regrows legs that have been-'

'Entirely the wrong track,' said the Sphinx, stretching its claws.

'Oh.'

'You haven't got the faintest idea, have you?'

'I'm still thinking,' said Teppic.

'You'll never get it.'

'You're right.' Teppic stared at the claws. This isn't really a fighting animal, he told himself reassuringly, it's definitely over-endowed. Besides, its bosom will get in the way, even if its brain doesn't.

'The answer is: “A Man”,' said the Sphinx. 'Now, don't put up a fight, please, it releases unpleasant chemicals into the bloodstream.'

Teppic backed away from a slashing paw. 'Hold on, hold on,' he said. 'What do you mean, a man?'

'It's easy,' said the Sphinx. 'A baby crawls in the morning, stands on both legs at noon, and at evening an old man walks with a stick. Good, isn't it?'

Teppic bit his lip. 'We're talking about one day here?' he said doubtfully.

There was a long, embarrassing silence.

'It's a wossname, a figure of speech,' said the Sphinx irritably, making another lunge.

'No, no, look, wait a minute,' said Teppic. 'I'd like us to be very clear about this, right? I mean, it's only fair, right?'

'Nothing wrong with the riddle,' said the Sphinx. 'Damn good riddle. Had that riddle for fifty years, sphinx and cub.' It thought about this. 'Chick,' it corrected.

'It's a good riddle,' Teppic said soothingly. 'Very deep. Very moving. The whole human condition in a nutshell. But you've got to admit, this doesn't all happen to one individual in one day, does it?'

'Well. No,' the Sphinx admitted. 'But that is self-evident from the context. An element of dramatic analogy is present in all riddles,' it added, with the air of one who had heard the phrase a long time ago and rather liked it, although not to the extent of failing to eat the originator.

'Yes, but,' said Teppic crouching down and brushing a clear space on the damp sand, 'is there internal consistency within the metaphor? Let's say for example that the average life expectancy is seventy years, okay?'

'Okay,' said the Sphinx, in the uncertain tones of someone who has let the salesman in and is now regretfully contemplating a future in which they are undoubtedly going to buy life insurance.

'Right. Good. So noon would be age 35, am I right? Now considering that most children can toddle at a year or so, the four legs reference is really unsuitable, wouldn't you agree? I mean, most of the morning is spent on two legs. According to your analogy' he paused and did a few calculations with a convenient thighbone- 'only about twenty minutes immediately after 00.00 hours, half an hour tops, is spent on four legs. Am I right? Be fair.'

'Well-' said the Sphinx.