It may not be a milestone birthday but turning 42 has inspired one writer to consider the meaning of life...

(Alamy)

1. I was counting on my 42nd birthday to enlighten me about life, the universe and everything. Or anything. But until that happens, this is all I've got.

2. People say age is just a number, and I suppose that's true, but it's a number that tells you roughly how far you are from death.

3. On a wall at home, I have a New Yorker cartoon by Bruce Eric Kaplan. Two cows are in a field and one is saying to the other: "I suppose if I'm really honest with myself I'm not totally fine about being slaughtered."

4. I was about 17, sitting on the sofa at my parents' house, watching TV in my pyjamas, fresh out of the bath, when I realised I was mortal. I can't remember what, if anything, prompted this chilling little epiphany. I didn't say anything to my parents. Dynasty was on.

5. There's been a lot of death in this piece so far and we're only at number five. Sorry about that. It's been on my mind. My father died just over a year ago. He left us just a few months before my wife gave birth to what would have been his first grandchild. That was terrible timing. Then again, if he'd met our daughter, leaving the world behind would have been even more of a wrench.

6. Anyway, thinking about death – something we tend to do more of the further we get from birth – makes me cheerful. It's ridiculous that a preoccupation with death is associated exclusively with heavy black eyeliner and dread. Reminding myself that's there's only so much time left makes me makes me hungrier for life.

Life’s surprising gifts: the author with daughter Io

7. "You ask me what life is?" said Chekhov. "That's like asking what a carrot is. A carrot is a carrot and there's nothing more to know." It's a little known fact that Chekhov invented Bugs Bunny.

8. We don't want to know how Lost or Breaking Bad ends until we've seen it, which is understandable, but the deep aversion  we feel when we think someone is about to spoil an ending is surely connected to how we feel about our own end. Death is the ultimate spoiler.

9. When I interviewed TV producer and wise man John Lloyd last year, I told him that my wife and I were expecting our first child, and he told me that we should think of our baby as a superior life form from another planet, sent to tell us things. I think this is very good advice. Although, it sometimes hard to credit when she's trying to eat a chair.

10. I'm OK with not finishing a book these days. In fact, I now think it's not OK not to give up on a book if you're not enjoying it. It's the thought of the book you're not reading that should pain you.

11. If you do not love Joe Biden, you do not love humanity.

12. The best things in life are difficult. Unless there is at least something in your life that is complex and challenging and forces you to adapt – learning the piano, running a business, raising a family – you're not awake.

13. Why not take something straightforward and complicate it needlessly? Thomas Mann: "A writer is someone for whom writing is more difficult than it is for other people."

14. Stress is underrated. When you put stress on your muscles, they grow back stronger. When you put yourself in stressful situations, you emerge a bigger person. I went freelance in my first career so that I could start a second career, in writing. That entailed stress. I did it because I didn't feel stressed enough by my job.

Ian Leslie with his father, who died just over a year ago

15. Note that I said "put yourself" in stressful situations. Being stressed by events over which you have no control is awful.

16. I divide books that I don't finish into categories: those that aren't good enough, and those for which I'm not yet good enough.

17. After more than three decades of reading, I still stumble over "latter" and "former" and have to double-check which is which.

18. All food tastes better once it's been out of the fridge for an hour. This may be the only useful thing I tell you.

19. You can get through life without knowing much. An acquaintance of mine, an intelligent man, is so complacent about the fact he doesn't know much about anything that he has made himself stupid. He's like an inverted polymath: his ignorance is multi-disciplinary and constantly expanding. He's perfectly happy.

20. I don't generally recommend being anxious, but I do recommend being anxious about what you don't yet know. Why don't you know more about the Ottoman Empire, or the structure of crystals, or the way houses are built? There are books, there are people, and now there's the internet. You're all out of excuses.

21. All else being equal, it's better to do things than not do things.

22. Empathy beats sympathy. Sympathy is where empathy starts, but it is unintentional, automatic – one string dumbly vibrating in reaction to another. Empathy requires an effort. It's difficult. Most of us don't bother with it.

23. The closer you get to the boundaries of social acceptability in any conversation with a new acquaintance, the more interesting that conversation will be. This is a great rule to bear in mind if you want more interesting conversations. But it comes with a massive caveat. You should never, ever seek to apply this rule when drunk. Unless the other person is equally drunk.

A young Ian: 'When you’re younger, you want to spend time doing fun things. As you get older, you realise that the boring bits are the point'

24. A more reliable principle is: everyone has something interesting to tell you, and the quickest route to it is to find out what they truly care about and know about, and talk about that.

25. Though, of course, you may not always want interesting conversations. The conversation you have with a stranger on the bus or with a colleague in the elevator should be as uninteresting as possible.

26. At my father's funeral, old friends recalled his characteristic opener to conversation: a smile, a name, a topic and a prompt. "Chris! The reshuffle. What do you think?" This is a pretty good way to start a conversation with a friend.

27. My dad took delight in people, and returned it. This is a gift, and a wonderful one.

28. Do you know what the odds were of you coming to exist, as you are? Vanishingly small. Eye-of-a-needle small. So remind yourself, when things aren't going well, that you're playing with the house's money. They let us in. I don't believe in an afterlife, but I do believe in heaven.

29. Our daughter's name is Io. We named her after – well, we're not entirely sure. Was it the moon of Jupiter, or the Greek nymph, or both? We loved the sound of it, and its elemental simplicity: a line and a circle. But one thing of which it has made us acutely aware is that these days the world runs on sans serif. People who have only read her name on email or SMS or Facebook greet her as "Lo". For this and for many other reasons, I implore you to join me in overthrowing the joyless tyranny of sans serif.

30. One of my favourite things about having a baby is the happiness she brings to strangers. It makes me believe that people are basically lovely.

31. A man in the street gave my wife a pound coin for our baby. I mean, he wasn't trying to buy her, he just wanted to give her something. My wife said no, but he insisted. We still have it. We may give it to Io when she is grown up and inflation has eroded the value of the coin to nothing. She won't thank us for it.

32. I cradle my baby in my arms and I think, one day you'll be looking after me.

33. Artistic canons are the best way to cope with the shortness of life and the anxiety of choice. I listen to more of Bach, Mozart, Elvis and Dylan than I do to this year's Top 50, and I'm more likely to read Nabokov or Fitzgerald than a new novel. They haven't survived the centuries, or the decades, by accident. You can be more confident than you can with this year's prizewinners that you're not wasting your precious time.

34. I don't trust my tastes too much. Personal tastes can change and grow. I try to make my tastes fit the great stuff, not the other way around.

Leslie says: 'I cradle my baby in my arms and I think, one day you'll be looking after me'

35. Elvis didn't die when he joined the army. He peaked around 1968-1970. In fact, listen to "Good Time Charlie's Got the Blues". "You know my heart keeps telling me/You're not a kid at 33/Play around you lose your wife/Play too long you lose your life."

36. Montaigne tells a story about a philosopher advising a king. "What are you going to do now?" asks the philosopher. "Conquer Italy," replies the king. "What are you going to do after that?" asks the philosopher. "Conquer Africa." "And after that?" "I'm going to conquer THE WORLD!" "OK," says the philosopher. "After the world is conquered, what then?" "Then," says the king, "I will sit down and savour a good glass of wine." The philosopher says: "Well, why don't you just have that glass of wine now?"

37. When you're younger, you want to spend as little time doing boring things as possible and as much time doing fun things as possible. As you get older, you realise that the boring bits, or the bits you thought of as boring, are the whole point. The people who charge through their forties and fifties furiously avoiding boredom look haunted.

38. My favourite description of marriage comes from a married friend who was advising me to go for it. "It's mundanity. But it's beautiful mundanity."

39. Io is always busy, wobbling off on some mysterious task, falling over and getting back up and falling over and setting off again, like a highly dedicated drunken postal worker.

40. Seraphically well-tempered during the day, she saves up all her rage for a black hour before sleep. We've given up trying to work out why. I've decided it's because she loves being awake so much.

41. In the morning, when Io joins her sleepy-headed parents, she crawls all over us, blowing raspberries; not just happy, but vibrating with joy. During the day, she emits random whoops of jubilation, chesty exhalations of pleasure, and sometimes a noise that sounds like a fox on heat. From her pram, she squeals at strangers as they pass, and they grin back, surfacing for a moment from internal monologues about what's in the fridge for this evening.

42. So I think maybe I know what Io was sent to tell us: wake up, wake up, you idiots! We made it.