According to the American Psychological Association, Americans “own twice as many cars per person, eat out twice as often and enjoy endless other commodities that weren’t around” in 1957 – “big-screen TVs, microwave ovens, SUVs and handheld wireless devices, to name a few.”

Yet we are LESS happy, according to a variety of studies, than we were six decades ago.

Frank Capra explored materialism in his classic 1938 movie, “You Can’t Take It With You.” The main character is an old fellow played by Lionel Barrymore. Friends and neighbors refer to him as “Grandpa.” It took him a lifetime, but in his early 70s, he knows what is really important in life.

Thirty years earlier, Grandpa had been an up-and-coming businessman. He was on his way to acquiring great wealth. One day, after riding an elevator to his top-floor office, he didn’t get out when the doors opened.

Something snapped in him.

He took the elevator back to the lobby, left the building and never returned. Instead, he used the money he had saved, a modest amount, to fund a world of beauty and creativity within the colorful home where he and several others lived.

His daughter is a mystery writer who taps continuously on her typewriter in the living room. His son-in-law invents rockets and fireworks in the basement. Another inventor living in the house had come to deliver ice 15 years earlier and never left.

Grandpa’s grandson-in-law is a musician and also an inventor. His granddaughter is a dancer whose Russian teacher never misses a free dinner at the home. Another fellow had been a frustrated bookkeeper, but Grandpa talks him into quitting his job so he can work full-time making scary rubber masks.

The plot thickens when a rich businessman tries buying Grandpa’s house. The businessman has plans to tear down the neighborhood to build a factory and get richer, but Grandpa refuses to sell – even though he is offered four times the value of the house.

All sorts of amusement and chaos take place, but toward the movie’s end, Grandpa finds himself in trouble with the law – for making unlicensed fireworks and disturbing the peace when the fireworks go haywire. Dozens of neighbors and friends, whom Grandpa has helped over the years, arrive and collect all the money they have to bail Grandpa out of jail. The rich businessman comes around in the end and realizes that “you really can’t take material possessions with you.”

But don’t we all know this – and keep forgetting it? We keep building massive houses, buying cars we don’t need and can’t afford, and racking up credit-card debt to buy more stuff.

Like Grandpa, we know that the happiest moments in our own lives involve friends and family – people we love. These are the people who affect the deeper parts of our nature – our spirits and souls – where true happiness resides. These are the people who can make us laugh so hard our guts hurt, help us when we’re down and engage us in deeply satisfying conversations.

The Mayo Clinic confirms this obvious truth. Its research finds that “people who are happy seem to intuitively know that their happiness is the sum of their life choices.”

People who are happy do five things that Grandpa did: They devote time to family and friends, appreciate what they have, maintain an optimistic outlook, feel a sense of purpose and live in the moment.  Grandpa was right. People and creativity and laughter make us happy – not the material junk that we can’t take with us.

Tom Purcell, author of “Misadventures of a 1970’s Childhood” and “Wicked Is the Whiskey,” a Sean McClanahan mystery novel, both available at Amazon.com, is a Pittsburgh Tribune-Review humor columnist and is nationally syndicated.