According to Rolf Dobelli, the answer is ... nothing.
"We do not know what makes us happy or successful," the author of "The Art of Thinking Clearly," told The Huffington Post in an interview. "But we do know for sure what destroys success, what destroys happiness." So the key to happiness starts with de-cluttering: The removal of all the things that makes us feel more drained than delighted.
While many happiness gurus champion so-called positive thinking, Dobelli suggests that negative knowledge -- knowing what not to do -- can be much more powerful. This de-cluttering can be material, but it is often ideological: If we can change our thinking to reflect this mental de-clutter, Dobelli says we're more likely to be productive. Most of the time, the author says, adding gadgets and practices we think will bring more to our life only ends up weighing us down.
Want to learn more? Below are five of his philosophies for discovering happiness (or rather, ridding distress). Read on and then, tell us in the comments what you think about these principles.
1. Know That Human Beings Are Extremely Bad At Forecasting Happiness
When you are bursting to buy that shiny, new car, know that the happy high you're experiencing is a fleeting one. In fact, Dobelli says that jubilant sensation you get from a big, material purchase will only last for up to six months, so buy wisely. "Be very careful," Dobelli warns, "generally, things do not make us happy, experiences, tasks, challenges and projects do." In other words, try to rid the desire for instant gratification -- some things are worth the wait.
2. Remove The Notion That 'Life Is A Dance'
"If you live like there's no tomorrow, you'll be in jail five minutes later," Dobelli laughs. The author says it's important to plan -- doing the hard thing now will make life easier in the long run. "Forget that carpe diem thing," he suggests, and realize that life takes effort, planning and forethought to be excellent. Don't let this tip get you down, spontaneity lovers -- the chapter this ideology comes from is titled "Live Each Day as If It Were Your Last -- but Only on Sundays." There's room to let your plans fall by the wayside: Doing so may seem like an oxymoron, but you're best scheduling unplanned days for once a week.
3. Stop Following The Herd
We're hard-wired to copy our peers; it's a habit we developed thousands of years ago when, if you saw your fellow caveman running from a sabertooth-tiger, it was wise to play copycat. In modern times, however, Dobelli says we benefit from straying form the pack: The action forces us to be more confident in our own decision-making. "Following the herd is very dangerous," Dobelli says. "The more we observe other people displaying a behavior, the more we think that behavior is right -- and that's absurd." Trusting your gut, and removing the influence of other's from what you decide is right, will get easier over time -- you just have to keep at it.
4. Limit Your News Consumption
Dobelli is an advocate of unplugging: He says rather than keep an eye on a steadfast Twitter feed, it's more productive to read books and long-form articles that will educate you on the bigger picture. The specific details that come from breaking news, like how long a storm lasted, are "not relevant to your life," the author says. Instead, invest your time learning about definitive concepts and events. Think you'll be accused of living under a rock? "I've never missed a beat," says the author. You'll hear about the news from your peers, he assures, but will still be in control of curating the way you consume it. Removing yourself from the clutter of the details will leave room for what really matters -- and what's worth spending your brain power on.
5. Don't Get Overly Caught Up In The 'Present Moment'
"Be in the moment" has become a pervasive mantra of those who subscribe to healthy and mindful living. But being present encapsulates both what you can and cannot see, Dobelli explains, and the latter is the part most people forget about. "We tend to be overly enthralled by the things that are here, and we don't have a sensor for the stuff that is missing," he says. Don't pigeonhole your day; instead, be cognizant that while things are happening before your eyes, things are also happening beyond them. It's a vague philosophy, but reminding yourself to be less egocentric can help remove the wasteful thoughts that come with being too "now"-minded.