We live in a town with three beaches. There are two parks less than 10 minutes' walk from home where neighbourhood children gather to play. However, what my children want to do after school is pick up a screen — any screen — and stare at it for hours. They are not alone. Today's children spend an average of four and a half hours a day looking at screens, split between watching television and using the Internet.

In the past few years, an increasing number of people and organisations have begun coming up with plans to counter this trend. A couple of years ago, film-maker David Bond realised that his children, then aged five and three, were attached to screens to the point where he was able to say "chocolate" into his three-year-old son's ear without getting a response. He realised that something needed to change, and, being a London media type, appointed himself "marketing director for Nature". He documented his journey as he set about treating nature as a brand to be marketed to young people. The result was Project Wild Thing, a film which charts the birth of the Wild Network a group of organisations with the common goal of getting children out into nature.

"Just five more minutes outdoors can make a difference," David Bond says. "There is a lot of really interesting evidence which seems to be suggesting that if children are inspired up to the age of seven, then being outdoors will be a habit for life." His own children have got into the habit of playing outside now: "We just send them out into the garden and tell them not to come back in for a while."

Summer is upon us. There is an amazing world out there, and it needs our children as much as they need it. Let us get them out and let them play.

There is something to be said for being a generalist, even if you are a specialist. Knowing a little about a lot of things that interest you can add to the richness of a whole, well-lived life.

Society pushes us to specialize, to become experts. This requires commitment to a particular occupation, branch of study or research. The drawback to being specialists is we often come to know more and more about less and less. There is a great deal of pressure to master one's field. You may pursue training, degrees, or increasing levels of responsibility at work. Then you discover the pressure of having to keep up.

Some people seem willing to work around the clock in their narrow specialty. But such commitment can also weaken a sense of freedom. These specialists could work at the office until ten each night, then look back and realize they would have loved to have gone home and enjoyed the sweetness of their family and friends, or traveled to exciting places, meeting interesting people. Mastering one thing to the exclusion (排除) of others can hold back your true spirit.

Generalists, on the other hand, know a lot about a wide range of subjects and view the whole with all its connections. They are people of ability, talent, and enthusiasm who can bring their broad perspective (视角) into specific fields of expertise (专长). The doctor who is also a poet and philosopher is a superior doctor, one who can give so much more to his patients than just good medical skills.

Things are connected. Let your expertise in one field fuel your passions in all related areas. Some of your interests may not appear to be connected but, once you explore their depths, you discover that they are. My editor Toni, who is also a writer, has edited several history books. She has decided to study Chinese history. Fascinated by the structural beauty of the Forbidden City as a painter, she is equally interested to learn more about Chinese philosophy. "I don't know where it will lead, but I'm excited I'm on this pursuit."

These expansions into new worlds help us by giving us new perspectives. We begin to see the interconnectedness of one thing to another in all aspects of our life, of ourselves and the universe. Develop broad, general knowledge and experience. The universe is all yours to explore and enjoy.

    Returning to a book you've read many times can feel like drinks with an old friend. There's a welcome familiarity — but also sometimes a slight suspicion that time has changed you both, and thus the relationship. But books don't change, people do. And that's what makes the act of rereading so rich and transformative.

    The beauty of rereading lies in the idea that our bond with the work is based on our present mental register. It's true, the older I get, the more I feel time has wings. But with reading, it's all about the present. It's about the now and what one contributes to the now, because reading is a give and take between author and reader. Each has to pull their own weight.

    There are three books I reread annually The first, which I take to reading every spring is Emest Hemningway's A Moveable Feast. Published in 1964, it's his classic memoir of 1920s Paris. The language is almost intoxicating (令人陶醉的), an aging writer looking back on an ambitious yet simpler time. Another is Annie Dillard's Holy the Firm, her poetic 1975 ramble (随笔) about everything and nothing. The third book is Julio Cortazar's Save Twilight: Selected Poems, because poetry. And because Cortazar.

    While I tend to buy a lot of books, these three were given to me as gifs, which might add to the meaning I attach to them. But I imagine that, while money is indeed wonderful and necessary, rereading an author's work is the highest currency a reader can pay them. The best books are the ones that open further as time passes. But remember, it's you that has to grow and read and reread in order to better understand your friends.