"Now and then I miss you," sing The Beatles, 45 years apart. AI has "lifted" John Lennon's voice from a 1978 cassette to reunite the Fab Four on their last song.¹

Ringo Starr and Paul McCartney are the surviving members of the 1960s foursome from Liverpool. The fourth, George Harrison, died in 2001.

They are the best-selling band of all time, shifting 600 million records.² The frenzy of Beatlemania followed them everywhere. They revolutionised pop, introducing classical, Indian and psychedelic music.

But can we compare McCartney's melodies to Mozart or Lennon's lyrics to Shakespeare? The Beatles were popular, but critics and experts have differing views on whether to take them seriously.

Musicologist Simon Frith says pop music is "designed to appeal to everyone" and is a commercialRun or maintained to make a profit. "enterprise not art".³ The purpose of pop music is to make you feel - not think. And there is evidence that it is getting dumber.⁴

The philosopher Theodor Adorno criticised popular music for sticking to a formula. Pop music comforts "the masses" but does not challenge society or its listeners.⁵ Writing in 1941, Adorno was thinking of jazz and swing.

But what would he have thought of Rubber Soul? The Beatles' rule-breaking and inspirational 1965 album. Expert James Decker wrote that it made listeners "desire and expect" more from music.⁶

McCartney says they try to "spread love" with their music. The former spy Leslie Woodhead believes The Beatles helped bring down the Soviet UnionOfficially the Union of Soviet Socialist Republics (USSR). A powerful group of communist republics, the biggest being Russia, that existed from 1922 to 1991. with their "spiritual energy".⁷ Lennon's Imagine made "catchy pop... utopianImpossibly perfect. The term comes from an ancient Greek phrase meaning "no-place" invented by Henry VIII's chancellor, Sir Thomas More, in 1516, as the name of an imaginary, ideal island. and deeply moral," says sociologist Phil Zuckerman.⁸

Popular music may be powerful in the moment - but trivialSilly or unimportant. and fleeting over time. Great art communicates truths about human nature.

But then, 15 billion miles from Earth, the Voyage 1 probe is the furthest human-made object from Earth. It contains a "golden record" for aliens to learn about us. Alongside Bach and Beethoven is Chuck Berry's 1958 hit Johnny B. Goode.

Critics told astronomist Carl Sagan this "adolescent" music did not belong on this serious mission.⁹ Sagan replied we want to tell aliens who we are, and "there are a lot of adolescents on the planet."

Yes: Something does not need to be complex to be serious. The power of pop is its universality. It brings people together in a shared appreciation of music. Only snobs would think that wasn't serious.

No: Pop is mindless rubbish. The music is predictable, and the lyrics are glibSpoken confidently but in an insincere or unserious way. and unimaginative. They are made to stick in our heads at the cost of thinking about anything serious or meaningful.

Or... The Beatles were not serious, and that was the point. They were irreverent, silly buffoons who mocked social conventions. We cannot always be serious, and we should enjoy the simple pleasures of pop.