No words capture the American dream like “I must be a soldier so my son can be a farmer and his son a poet.” Oft-repeated in varying versions, this catchphrase can be traced to a letter by John Adams to his wife, Abigail, in which the future president describes (at much greater length) the arc of a frontier society as it progresses from warfare to subsistence to the arts. But the history of pop music in this country, especially when it’s embodied in a band like the Beach Boys, prompts one to alter the message so it reads: “I must be a soldier so my son can be a farmer so his sons and their cousin can start a band and go from being penniless nobodies to wealthy international celebrities overnight.”

In 2012, the Beach Boys celebrated their 50th anniversary. The boys in the band began with nothing and then found themselves part of a massive shift in what it meant to be young and American.

Good Vibrations By Mike Love with James S. Hirsch Blue Rider, 436 pages, $28

Now two new books, each by a founding member, tell the story of the California band from the inside. Mike Love’s “Good Vibrations: My Life as a Beach Boy” is an up-and-down account of the band’s successes and travails from year to year; it’s detailed and occasionally bitter, for good reason. “I Am Brian Wilson,” on the other hand, is as plain-spoken as its title. Here the band’s presiding genius wanders over the terrain of his life as a son, father, husband and supremely gifted musician, describing what he remembers in a childlike tone. An ocean of ink has been spilled on the Beach Boys and their music, and these are not the best books on the subject; insider accounts (with the exception of Keith Richards’s “Life”) rarely are. But they are the latest books; they tell us much that we didn’t know; and together they lay out their shared joys and frustrations and suggest how we might best view the artistic life—any life, really.

Beach Boys co-founder Mike Love, author of the new memoir “Good Vibrations,” reveals inside stories about the group, bandmate Brian Wilson and the Beatles.

Mike Love follows a hallowed biographical plot by beginning before the beginning, describing both his sets of grandparents and then his musical mom and the hardworking dad whose family business, Love Sheet Metal, boomed during World War II but floundered during the recession of the late 1950s. In contrast to these sharp details, Brian Wilson begins his version of the Beach Boys saga, “It’s been hard and it’s been easy. Mostly, it’s been both.” A few sentences later, he writes: “I can’t always get a clear picture. Sometimes it’s pieces of pictures. It’s hard to get back to where you were, you know?”

Brian and his brothers, Dennis and Carl, prospered as musicians yet suffered emotionally and physically under another hardworking dad, the Murry Wilson who as their manager pushed them to be the best so relentlessly that he has become one of the all-time villains of stage parenting, cursing and even hitting the brothers in the studio and around the house. One of the constants of Beach Boys lore is that Murry deafened Brian’s right ear with a blow to the head; Mr. Love reports that, according to Brian’s mother, Murry struck young Brian with an iron while the boy was sleeping. But Brian himself says that a neighborhood kid struck him with a lead pipe while they were playing. Brian is typically ambivalent about the kid, yet he’s the same way about his father, calling him “generous” and “brutal” in the same sentence and saying that “lots of things about my dad are . . . two things at once, two opposite things.”

I Am Brian Wilson By Brian Wilson with Ben Greenman Perseus, 308 pages, $26.99

Out of this pressure cooker came the Beach Boys, the original early-’60s lineup of which consisted of the three Wilson brothers, their cousin Mike, and their friend Al Jardine. Like any pop group, this one did best when it connected with the Zeitgeist and withered as the public’s taste evolved and consumers moved on to newer music.

Given the longevity of the Beach Boys, a chart of their career would resemble a graph of the Dow Jones Industrial Average over several turbulent decades. “Our music merged with the idealism of the early 1960s,” says Mr. Love, and “helped define the era.” In the early ’60s, California became a sort of promised land to many, and the Beach Boys became its voice. “I can’t tell you how many people over the years have told me that they moved to California from Nebraska or Vermont or wherever because of the Beach Boys,” writes Mr. Love.

It didn’t hurt that this was also the era of John F. Kennedy and Lyndon Johnson; the Vietnam War hadn’t heated up yet, so it was still a time of great promise, of ending segregation and sending men to the moon. “Our music provided the soundtrack to a special time in American history . . . ,” according to Mr. Love. “But we weren’t part of some screenwriter’s nostalgic story line. We lived in that moment.”

The Beatles appeared as serious rivals when they came to America in 1964, but the way these books tell the story, the two groups inspired each other more than competed. Brian recalls that “God Only Knows” from “Pet Sounds” (1966) was one of Paul McCartney’s favorite songs, and he says that, after the album came out, John Lennon called him to say how much he loved it.

Then there was “Good Vibrations.” By 1966, Brian was more than ready to move the Beach Boys out of their surf-band phase, and he couldn’t have come up with a more radical departure than this ecstatic patchwork of “seemingly unrelated snatches of music,” as Mr. Love says. Issued as a stand-alone single with Brian Wilson’s music and Mike Love’s lyrics, today “Good Vibrations” is on just about every music journalist’s list of the best songs ever.

But by 1968, “madness had become the norm,” says Mr. Love, and fans wanted songs about antiwar protests and drug use. They wanted the Doors, Cream, and Hendrix, in other words, not a band made up of clean-cut guys in matching shirts. By the mid-’70s, though, the Beach Boys were back, riding a wave of nostalgia along with movies like “American Graffiti” and the sitcom “Happy Days.”

The band’s reputation for songs about cars, surfing and teenage crushes somehow escaped Interior Secretary James Watt, who canceled a Washington appearance in 1983 because of fear that the group’s “hard rock” would attract “the wrong element” and encourage “drug abuse and alcoholism.” The Reagans made up by inviting the boys to play at the White House. Troubled by mental issues, Brian had long since stopped touring with the band to spend his time composing and was replaced on the road by Bruce Johnston, who could hit Brian’s high notes. In 1989, Mr. Love and Mr. Johnston worked with President George H.W. Bush to start a community-service curriculum in schools. Their association with the Reagans and Bushes has led some to think of the Beach Boys as the house band of the Republican Party, but as Mr. Love says, they’d have played for the Democrats, too, if only the Democrats had asked.

Even the group’s travails often seem uniquely bound to the times. In Brian’s case, there was the off-and-on presence of the Svengali-like guru Eugene Landy, the psychotherapist whose insistence on total control helped and then haunted the troubled artist. (“Though he had gotten me stronger back in 1976, by . . . the ’80s he was only making me more afraid.”) The band’s drummer, Dennis Wilson, hung out with Charles Manson, a relationship to which, typically, Mr. Love dedicates an entire chapter and Brian dismisses in less than a page, concluding that “families can be the strangest, most horrible things.”

A less dramatic but more corrosive development was the persistent denial of credit to Mike Love for dozens of the 80 or so songs he wrote or co-wrote, including “California Girls” and “I Get Around.” Mr. Love suffered from the slipshod accounting practices of a new industry, but he was also victimized by Murry Wilson’s pigheaded incompetence. As you might guess, Mr. Love relates his understandable bitterness and eventually successful court battles in detail, whereas Brian barely mentions the decadeslong dispute and muses, “Mike was Mike.”

Today there are two separate acts on the road: “The Beach Boys,” including Mike Love and Bruce Johnston, and then simply “Brian Wilson,” the once-reclusive genius having overcome his shyness to appear these days with Al Jardine and other musicians. Most of the hatchets seem to have been buried. The best overall book on the musicians, and especially their leader and most gifted member, is still Peter Carlin’s “Catch a Wave: The Rise, Fall & Redemption of the Beach Boys’ Brian Wilson” (2006), an account that ranks up there with Bob Spitz’s magisterial “The Beatles” (2005).

But if Mike Love adds important factual detail to what we know, there is in Brian Wilson’s poker-faced acceptance a reminder to take life as it comes. Part of the charm of his account is the way he drops little moments into the story with no preamble and then moves on with no follow-through. Once, he says, he ran into Magic Johnson on a hiking path on Maui. “Hi, Brian,” said the basketball star. “Hey, Magic,” replied Brian. And then he writes, “I kept walking.”

—Mr. Kirby is the author of “Crossroad: Artist, Audience, and the Making of American Music.”