Jim asked kindly, 'Is it all in working order?'
     The boy forced himself to put the torch into Jim's big outstretched hand, to stand still and attentive while Jim gently twisted the barrel to make the bulb come on.
     'It's a good one,' said Jim, pointedly approving, handing it back.
     'Yes,' said the boy, forcing himself to acknowledge Jim's kindness and affirmation.
     But Jim is not his dad. "But that's just stupid," said Helen. "He'd just overtake it. He wouldn't stop."
     "Well, yes, of course, we know that something going fast can overtake something going slowly. Or we think we know, because we can observe it and it seems intuitively correct. Zeno was just pointing out that it's illogical, if you try to think about it mathematically. If you can go on dividing time and distance indefinitely, then in theory nothing could ever move at all, because no matter what point you move to when you start off you can imagine another point which is even closer."
     Helen was frowning. "Well, it can't be true, so it's just playing with words."
     "Maybe so, but then words are what we think with, so it's interesting to analyse them and see what assumptions we make."
     "I don't see the point in talking about things that aren't real."
     "What's real, though? If words aren't real, what is?"
     Helen shrugged. "I don't know. This bed, for example."
    
'It's a red one,' he tells his dad now. 'It's in my rucksack.'
     'Oh,' says his Dad, 'good, good,' a little distractedly, driving the car quickly, efficiently through the gate. His dad parks the car neatly, gets out smartly and shuts the gate.
     Some yards off on the tufted moor a scattered group of wild ponies lift their heads and sniff the air. One, dappled grey, moves with interest towards the car, man and boy.
     The boy is still in the car, tugging at his rucksack, fighting with stiff straps to get at the torch. As the man comes back and puts his head into the open door, he holds it up: 'Here it is!'in the time it took Achilles to close the intervening distance.
     When the boy stepped into the kitchen he saw her start with alarm and shame. He said, 'I found my torch.'
     'Oh good!' she said quickly, wrenching a look of bright enthusiasm onto her face.
     The light seeping through her fuzzy hair made the bones of his shoulders ache.