CARPE diem – seize the day – is one of the oldest philosophical mottos in Western history. First uttered by the Roman poet Horace over 2,000 years ago, it retains an extraordinary resonance in popular culture. Ask someone to spell out their philosophy of life and there’s a good chance they will say something like "seize the day" or "live as if there’s no tomorrow" – even if they appear to be trapped by routine or paralysed by procrastination.

It’s a message found in Hollywood films like Dead Poets Society, in one of the most successful brand campaigns of the last century ("Just Do It"), and in the social media hashtag #yolo ("you only live once"). Almost every language has an equivalent expression for the original Latin phrase. Carpe diem has been a call to arms for everyone from the Jewish sage Hillel the Elder, who in the first century bce asked, "If not now, when?", to the Rastafarian sage Bob Marley, who sang out: "Wake up and live!"

However, in the course of writing my new book on the vanishing art of seizing the day, I discovered that carpe diem has been hijacked – in part, by the most popular leisure pursuit in the Western world.

I loved television as a kid, fitting in an hour before school each day (Thunderbirds, Superheroes) and at least an hour-and-a-half before dinner (5.30: Wheel of Fortune, 6.00: The Goodies, 6.30: Dr Who).

What I didn’t realise as a teenager, as I sat on my beanbag in suburban Sydney making the agonising decision whether to break tradition and watch Gilligan’s Island instead of The Goodies, was that I was absorbed in a ritual that ranks as one of the most momentous cultural transformations ever experienced by humankind. Within less than 50 years of the first ever television demonstration in

Selfridges London department store in 1925, around 99 per cent of Western households had a set. Today the typical European or American watches an average of around three hours per day, whether it’s on flat-screen TVs, computers, phones or other devices. This is apart from time spent engaged in digital pursuits such as internet surfing, social media, texting or video games. So television takes up a full 50 per cent of our leisure time, and more time than we spend doing any other single activity apart from work or sleep.

Perhaps the best way to grasp how much TV has colonised our lives is to tape the following statistic to your remote control: assuming your viewing habits are somewhere near average, if you live to 75, you will have spent around nine years of your life watching television.

Let me try that again. Imagine being on your deathbed, gazing back at your life – the successes and failures, the loves, the regrets, the good times and bad. Nearly a decade of it will have been spent staring at the tube. I doubt many of us will look back and treasure the memories of watching reruns of The Big Bang Theory.

In a digital world, you might have thought that television no longer retains such a hold on our lives, and if anything threatens to hijack carpe diem, it is more likely to be all that time we spend fiddling with our phones and checking our social media feeds. But the time-use data reveals that TV remains by far the dominant force in our 24/7 digital existence. According to one of the most detailed studies of how much time US adults spend using different electronic devices, 12 per cent of the daily total is using a smartphone, 9 per cent on a PC, 4 per cent with a tablet and 18 per cent listening to the radio. And the figure that dwarfs them all? Television, at 51 per cent, which we watch at scheduled times and for which we increasingly use "on demand" or "catch-up" services.

It is true that people aged 18 to 35 tend

to watch less TV, and that much of the time people are watching they are also multitasking on other devices. But in general, even those addicted to checking their phones end up giving a sizeable chunk of each day to John Logie Baird’s wondrous invention of television. As a seminal report on teenage media use concluded, "even in this new media world, television viewing ... continues to dominate media consumption".

If I were to ask you to seize the day, right here and now, it is unlikely that you would switch on the television and start flicking through the channels. Most people recognise TV is a step removed from real-life experience. Carpe diem is about seizing experiences for yourself, not gazing at others seizing them on a screen. There is a big difference between going to a tango class and watching celebrities tango on Strictly Come Dancing. Similarly, your palms might sweat watching an exciting tennis match on TV, but it’s nothing like the sweat you get from running around a court yourself.

This point was powerfully made in the classic 1978 book Four Arguments For The Elimination Of Television, written by the former TV advertising executive Jerry Mander. "In one generation, out of hundreds of thousands in human evolution," he wrote, "America had become the first culture to have substituted secondary, mediated versions of experience for direct experience of the world." It had become normal to sit in front of a screen and spend a substantial portion of each day watching other people live their lives – or actors pretending to be other people – instead of living our own.

Wasn’t Mander going too far by branding television as an artificial activity distinct from genuine life experience? It is certainly true that watching TV is an experience of sorts. We engage our senses (at least our eyes and ears), and it can be a communal pastime – like when we go to a bar to watch a World Cup final or the Super Bowl. Also, due to digital recording and streaming technology, we now actively choose what to watch and when to watch it more than ever before.

In general, however, it is an unusually passive way of engaging with life. Sure, we might sometimes press a button that allows us to vote in a reality TV show, but most of the time we are just gazing at the screen, interrupted by snatched conversation during commercial breaks or sending a quick text to a friend. TV might be a great way to relax, it might make you laugh or cry, and it can certainly be more informative or enlightening than scrolling through Facebook updates. But it is a poor surrogate for the pulsating sense of aliveness and active engagement that is the essence of seizing the day.

For all the pleasures that television brings, it is difficult to avoid the conclusion that the sheer volume of second-hand experience that has come to occupy most people’s lives represents a colossal hijacking of our carpe diem potential. What is more, the three hours we dedicate to TV each day robs us of precious time that we could be using to do a multitude of other activities, whether it is learning to play the ukulele, training your dog to catch a frisbee, doing a daily meditation session, or inventing a new kind of solar panel in your back shed. You are unlikely to make much progress in any of these if your default evening activity is settling down in front of the television.

Would history’s greatest carpe diem adventurers, from Marco Polo to Amelia Earhart, have been TV addicts? I doubt it. They were addicted to the heady business of experiential living (though I’m sure Marco Polo would have been blogging and

tweeting on his journeys).

Might not a travel show inspire us to embark on a cycling expedition across the Sahara, or a creative children’s programme show kids how to make a fort out of lollipop sticks? Can’t TV motivate us to get up off the sofa and propel ourselves into life?

Yes … but only occasionally. Decades of research shows that television generally acts as an experiential soporific. Switching on the TV tends to switch us off from so much else. For a start, it’s bad news for our sex life: people with a television set in their bedroom have half as much sex as those who don’t. It makes us less active: heavy TV viewers tend to do less sport or physical exercise, especially if they are women. High television consumption is associated with low levels of civic and political engagement, for example in volunteering, voting and protesting. And it isn’t great for kids: pre-schoolers who spend lots of time looking at screens spend less time in creative play and constructive problem-solving.

One other small point I forgot to mention: television will kill you. During the course of my research I came across a startling article in the respected British Journal Of Sports Medicine that concluded: "On average, every single hour of TV viewed after the age of 25 reduces the viewer’s life expectancy by 21.8 minutes."

If anything was going to stop you seizing the day – or doing anything else – it would be premature death. But could this statistic possibly be true? Was watching an hour of Sherlock a veritable death sentence? What I discovered was a whole field of public health research, based on the study of 10s of thousands of people, proving over and again that TV viewing, and other forms of sedentary behaviour such as sitting at a computer all day, go hand in hand with increased risk of death, particularly from cardiovascular disease. Experts in preventative medicine are starting to recognise that human beings simply aren’t designed for long periods of sitting still. Doing so may, for instance, have a detrimental effect on how our bodies process fats and other substances, leading to greater risk of serious heart problems.

The curious thing about the above arguments is that they are unlikely to convince you to watch less television. The reason is that TV has powerful addictive qualities. People can have a strong sense that they should be watching less but find themselves unable to reduce their viewing time: surveys reveal that 40 per cent of adults and 70 per cent of teenagers say they watch too much TV, and 10 per cent of adults describe themselves as addicts. Researchers in Germany found that people who try to resist the urge to watch television fail around half the time, and are much better at resisting the desire to nap or snack. Other studies show that the longer people watch, the less enjoyment they get from it – yet they don’t have the willpower to switch it off even if the programme is boring. Think how many times you’ve come to the end of a programme or film and thought: "Why did I just waste my time watching that junk?" It happens to me more often than I’d like to admit.

Simultaneously stimulating and relaxing, watching television develops into an almost physiological craving: we become desperate for an injection on a daily basis. The addictive nature of television makes it disconcertingly similar to the happy drug soma used to dope up the inhabitants of Aldous Huxley’s Brave New World.

Of course we all need regular doses of relaxation. But might there not be other ways of relieving tension and anxiety – like a massage from your lover (if you can get it) or a long candlelit bath (if you can’t)? Isn’t it more fun to laugh with your friends than with the studio audience on TV?

Ultimately, is it really worth granting nine years of our precious existence to the second-hand pleasures of television when we might be having more direct experience of the world?

I’m not suggesting that we ought to abandon television entirely. Ever since the ancient Greeks invented public theatre, human beings have loved being entertained – that’s why I’ve just binged on the superb six-part BBC drama Wolf Hall. TV can be far more than entertainment too: I’m sure I learned a lot more about American society from watching The Wire than reading a bunch of sociology textbooks, and I wouldn’t want to give up the holy father-son bonding ritual of watching test cricket with my dad. But if we hope to bring more carpe diem into our lives, there may be no more obvious action to take than this: cut back the television hours and win back the seize-the-day opportunities that have been hijacked from us.

One of the best ways to break the television habit is to write down a list of easily available and enjoyable non-TV activities that you can consult each time you are about to perform the reflex action of switching on the television. Stick them to the screen with a Post-it note if necessary. It will force you into making a genuine choice: is watching this programme what I really want to be doing with my life at this very moment (it could well be) – or is there some better alternative?

This strategy sounds almost too artificial, but it could be the first tiny but significant step toward a life driven by a new habit: to just do it instead of just watch it. Dust off that ukulele and get ready to play.

This is an edited extract from Carpe Diem Regained: The Vanishing Art Of Seizing The Day by Roman Krznaric, published this week by Unbound, £14.99


Raised in Sydney and Hong Kong, Roman Krznairc is a social philosopher, author, and the founder of the world's first Empathy Museum and of the digital empathy Library.