Alistair is one of those easy-going friends where the conversation picks up where it left off, no matter how many days or weeks have gone before. A geologist by trade, his natural inquisitiveness extends endlessly, to everything, from dinosaurs to the Trump administration, computer hackers to the future of transportation – everything flowing one thing to another as bright and lively and refreshing as a spring from an artesian well. I don’t see Alistair so much these days, more’s the pity. We met dog walking, and that’s what I’ve come to do today, driving out to his new house in the country.

So after getting there early, pulling on our boots and discussing the route, we set off, his collie Ailsa running on ahead with Lola, our lurcher, trying to keep up. Briefly stopping to check on the two new chickens he’s added to his flock, in a pen at the bottom of the garden, we have the usual family updates neatly out of the way by the time we’ve reached a gap in the hedge, and the conversation opens out as we step through into the first field.

Religion

 ‘Do you think the whole religion thing just boils down to people being scared of dying?’ I say, stopping to take a photo of some ferns on an old wall.  ‘Or maybe it started off when people painted pictures of animals they hunted and then confused the picture with the real thing.’
‘I don’t know,’ says Alistair, examining a twig. ‘It’s such a world-wide phenomenon. It’s like a function of who we are. I read this book once that looked at religion in the context of societal development. It was a bit turgid, but I think he had a point.’
‘Which was…?’
‘Well to begin with you had groups of people wandering about, following the migratory routes and the seasons, settling in places only so long. You get an idea of how their religions might have looked from old peoples like the Native Americans or the Aborigines, where it’s all very much linked to the land, ancestors, spirit animals and so on. I mean, some things you can imagine. Like worrying whether the sun’s coming back, or thinking that lightning or earthquakes are the world being angry. But then as soon as people start settling in to one place, and they start being able to support themselves, and an artisan class, then the more monotheistic religions come in, which fit with the way society starts to stratify into working and ruling classes.’
‘Be content with your lot because your reward will be in heaven’
‘Exactly. And it sanctifies wars of acquisition, because God’s on your side, even though it’s obvious they’ve got a version on their side, too.’

We come to a pine tree that’s been pushed over by a storm. The roots have been levered up, so the bole looks like the door to the underworld prised open. I stop to take a photo whilst Alistair re-laces his boots.

‘Have you ever been to Jerusalem?’ he says. ‘I went there once – by accident – long story – but anyway, fascinating place. We went to Temple Mount, to see the stone Mohammed was supposed to have launched himself from to meet Allah. I was standing there with the rest of the crowd, and I was trying to get into it all – you know – the idea that here was something magical and divine. But I just couldn’t get past the thought that here we all were, standing round an outcrop of limestone on a bit of a tilt.’

Eyes

‘You’d think with evolution you’d see lots of redundant species,’ I say. ‘But you don’t. Everything seems finished. Although hammerhead sharks are pretty weird.’
‘I think the thing is, evolution happens over such a long period of time, and at a genetic level, it’s hard to comprehend,’ says Alistair. ‘But then – think of the spectacular variations you get in eyes. It’s such a specialised bit of kit, adapted for all kinds of environments. Flounders, lying on the sea bed facing up. Or flies, with compound eyes that look like blackberries.’
‘I think I read somewhere that a hawk has two lenses in each eye, one for distance, one for close up.’
‘And dogs. Dogs have way more peripheral vision than we do because they needed it for the plains. And that’s why they tilt their head to look at you. Not because they’re trying to be cute. They’re just trying to get past the end of their nose to read your expression better.’

We come to an overgrown railway bridge, abandoned years ago along with hundreds of other branch lines in the sixties. It’s a poignant scene, and seems to fit with the idea of evolution, redundancy, for better or worse.

Left brain, right brain

‘You know swifts?’ I say, stopping to take a picture. ‘Apparently they live almost their whole life on the wing. When they want to sleep, they fly up ten thousand feet, then half their brain shuts down, with the other half adjusting to the wind currents so they stay in the same place.’
‘The whole sleep thing’s interesting,’ says Alistair. ‘I mean – this idea that you close down for hours, in some kind of suspension. I think there’ve been studies done that show if you hear a regular noise you don’t respond, but if you hear something sudden and out of character, you wake up. So you’re actually monitoring your environment – which suggests you’re never completely out. Which makes sense.’
‘Maybe that’s why your brain’s in two halves, so one half can keep an eye on things while the other rests.’
‘There’s definitely something in this whole symmetry thing. Two arms, two legs, two sides of the brain. I don’t know. It kind of fits with the rest of the design.’
‘Didn’t they debunk that whole left brain, right brain thing?’
‘It’s over-played. You get regions responsible for different tasks, and it all comes together. It’s like eyes again. The two inputs merging to give you a stereoscopic picture. It’s probaly something like that. A kind of rounded, three-dimensional apprehension of whatever it is you’re thinking about…’

You are old, father william

We meet an elderly man at a gate, out walking his large, chocolate labrador. The man looks a country sort – gilet jacket with loops for shotgun shells, and a small pair of binoculars. We stop to chat, but Alistair’s from Edinburgh, and his accent completely flummoxes him. Hmm? he says, and then looks at me to translate. Alistair asks him whether he’s spotted anything interesting whilst he’s been out. The man looks to me again. I point to the binoculars.
‘I’ve got a defibrillating pacemaker,’ he says, as if that’s what I could have possibly meant.
‘Oh?’ I say.
He goes on to describe in great detail absolutely everything pertaining to his heart condition. The number of times surgery was cancelled, even though a wire was actually hanging loose, he says.
‘And picking up a local taxi cab’ says Alistair.
Hmm?
I don’t translate. He carries on… the dose adjustments to his Warfarin, transport arrangements, failures, symptoms out walking, and on and on. It’s an exhaustive and comprehensive account. Ten minutes later and the dogs have given up, going on into the next field to sniff about, and even though I keep glancing in their direction and making slight movements of my body to hint that perhaps we should follow, and it’s all been lovely, the man carries on talking. I start to feel desperate and consider my options, but Alistair seems happy enough, standing with his arms folded, listening to the man, drinking it all in. Eventually, through some miracle not of our making, the man runs aground.
‘…but I mustn’t keep you,’ he says. ‘Cheero!’ and abruptly hooking his labrador to him with the crook of his walking stick, he turns and shuffles off.

‘You see!’ says Alistair, utterly unfazed. But I’ve completely lost the thread, and I’m not sure I do.