When scientists tracked hundreds of men for decades to uncover the secret to lifelong flourishing for the biggest happiness study ever conducted here's what they concluded:

"Happiness is love. Full stop."

What's more, a solid partnership won't just make you happier. Research also shows that a happy relationship will help you get ahead at work too.

So if supportive, long-lasting love is so essential for happiness and success, how do you get it? For centuries, everyone from psychologists to poets have spilled thousands of gallons of ink over this question, but Cornell gerontologist Karl Pillemer believed there was still one relatively untapped well of wisdom on the subject -- older folks with decades' of marriage under their belts.

Hoping to mine seniors for relationship advice, Pillemer gathered some 700 individuals who had been married for more than 30 years and asked them for their most crucial marriage advice. The oldest couple in the study was 98 and 101 and had been married 76 years; together the participants had a collective 40,000 years experience with marriage. (Pillemer pulled together similar groups for studies on careers and regrets as well).

What did they tell Pillemer? There's a whole book on his findings if you're looking for a deep dive, but the basic advice boils down to sensible tips you might have already heard from your mom (hat tip to Big Think for the pointer). But just because they're straightforward, doesn't mean they're not also incredibly powerful.

1. Learn to communicate.

"For a good marriage, the elders overwhelmingly tell us to 'talk, talk, talk.' They believe most marital problems can be solved through open communication, and conversely many whose marriages dissolved blamed lack of communication," says Pillemer (and just about every other relationship counselor ever.)

2. Get to know your partner very well before marrying.

The seniors Pillemer spoke with were not fans of whirlwind romances. "Many of the elders I surveyed married very young; despite that fact, they recommend the opposite. They strongly advise younger people to wait to marry until they have gotten to know their partner well and have a number of shared experiences," he notes.

As a corollary to this point, the seniors also insisted you should "never get married expecting to be able to change your partner."

3. Treat marriage as an unbreakable, lifelong commitment.

"Rather than seeing marriage as a voluntary partnership that lasts only as long as the passion does, the elders propose a mindset in which it is a profound commitment to be respected, even if things go sour over the short term. Many struggled through dry and unhappy periods and found ways to resolve them -- giving them the reward of a fulfilling, intact marriage in later life," says Pillemer.

4. Learn to work as a team.

According to the senior citizens Pillemer talked to, there is no such thing as an individual problem in a happy marriage. Instead it's all for one, and one for all:

"The elders urge us to apply what we have learned from our lifelong experiences in teams -- in sports, in work, in the military -- to marriage. Concretely, this viewpoint involves seeing problems as collective to the couple, rather than the domain of one partner. Any difficulty, illness, or setback experienced by one member of the couple is the other partner's responsibility."

5. Chose a partner who is very similar to you.

This is probably the bit of advice that's the easiest to argue with, but the seniors in this study insisted that "marriage is difficult at times for everyone... but it's much easier with someone who shares your interests, background and orientation. The most critical need for similarity is in core values regarding potentially contentious issues like child-rearing, how money should be spent and religion."

Do you agree that opposites attract is a recipe for a rocky marriage?