You called Samuel Johnson “the patron saint” of your book The Happiness Project. Let’s start by discussing Boswell’s classic biography.

Samuel Johnson has such insight into human nature. His devoted fan and friend James Boswell wrote The Life of Samuel Johnson. It's charming to read. He had so much to say about self-knowledge and what it means to be happy. In the book, he quotes a Spanish proverb that was well known in his time: “He who would bring home the wealth of the Indies must carry the wealth of the Indies with him.” I came to feel that it had enormous meaning for happiness, that I could only find it if I brought it.

Johnson, an eccentric 18th century lexicographer, essayist and editor, is the patron saint of my happiness project in that I am guided by his epigrams. He wrote, “Grant me God to resolve a right and to keep my resolutions”. He made and broke resolutions throughout his whole life and yet always came back and tried to do more. And he has this great line: “No money is better spent than what is laid out for domestic satisfaction.” I’m an under-spender, so this one helps me break out the wallet to fix the blender. I am basing my next book on his epigram, “to be happy at home is the ultimate result of all ambition”. When you think about all the different elements of life, being happy at home is most important.

Johnson formed a social group called “The Crowd” that eventually included Joshua Reynolds, Edmund Burke and Adam Smith. I understand research shows that strong social relations support happiness.

Benjamin Franklin did something very similar. One of my most successful happiness project resolutions is to join or start a group because, as you say, strong relationships with other people are the key to happiness. Being part of a group is an efficient way to maintain a lot of relationships; social networks are stronger than isolated relationships. If your group is formed around something that you feel passionate about, it's also a way to make sure that you spend time on what gives you pleasure.

People are so busy they don’t make time for things that are important to them. Since I started my happiness project I've joined or started something like 15 groups. My favourite groups talk about young adult literature. I thought I might be the only adult in New York City who would want to do this, but the first group got so big it had to close to new members. I started a second group and then a third.

Benjamin Franklin's autobiography is your next choice. Please tell us what it taught you about happiness.

I copied Franklin in my own book. He believed that we all could determinately sit down and come up with practical steps to make changes in our life. He identified 13 virtues that he wanted to imbue in himself and made a weekly chart to help him track his daily progress. I copied my resolutions chart from him.

Franklin was incredibly polymathic. He was an author, a printer, a diplomat, a postmaster, an inventor.

Franklin’s life teaches us that when you love what you do and your life reflects your values, you can accomplish an unimaginable amount. What I found in my own modest attempt to follow in his footsteps is that if what I do really reflects what I want to do and like to do, instead of what I think I ought to do or what seems like it would be the smart thing to do, than I am happier and more successful. When you see someone who seems to accomplish a superhuman amount, I think it's because they’re doing what comes naturally.

Next, Story of a Soul is the posthumously published autobiography of a French Carmelite nun who died of tuberculosis at age 24 in 1897. Did you receive this at your first communion?

I'm not Catholic so I had never heard of St Therese, which is like not knowing about the Beatles. She's a superstar saint. I had been reading Thomas Merton's Seven Story Mountain, his own spiritual memoir, and he mentioned “the little flower”. I was so surprised that this macho grouchy guy wrote with reverence about this young woman. She lived in a cloistered convent in France where several of her biological sisters became nuns.