Everyone has a favourite Beatles song. To their millions of fans the Fab Four's hits were innocent pop tunes about love and life in the 1960s. No harm in that.
But to Bob Mason they mean much more. He says the lyrics of their most popular early songs actually show an underlying tension between John Lennon and Paul McCartney.
Mason, 43, is studying the Beatles through a 125,000 word doctoral thesis in history with the title Magic Circles at Monash University.
Lennon may have been a working-class hero to his fans but to Mason he was very much a middle-class lad with an unhealthy obsession for money - a fixation McCartney despised.
Mason, a financial services analyst, has closely examined the lyrics of songs up to 1966. Later Beatles' songs were more overtly autobiographical and Lennon is widely held to have expressed his disdain for McCartney after the Beatles split, particularly in songs on the album Imagine.
But Mason says tensions were apparent even on an early cover of "Money", the Gordy-Bradford song the Beatles used to close their second album, With The Beatles.
"You can see how the fundamental issues that were dividing Lennon and McCartney were being fought out even at that stage," Mason says. "You can actually see how each one's personality is reflected in the songs that were written. How they took positions against, or relative to, the other person."
He says Lennon "typically overwhelms McCartney in argument" and McCartney "overwhelms Lennon in music".
The thesis examines several themes including songs related to departure.
"One of the things I looked at was how the Beatles were concerned about money," says Mason, who is confident his work will be published.
He says Lennon's preoccupation with cash was evident from "the standout song" on the second album, the cover of "Money".
"There's no altruism in it," he says, quoting lines from the song: You say that money can't buy everything/What it can't buy I don't need/Just give me money/That's what I want.
"It was looked at, at the time, and I think now is still regarded as perhaps the most outstanding recording that the Beatles ever did," Mason says citing early performances at the famous Liverpool venue, "that captured the full power of their Cavern Club performances".
He says Lennon loved the song and sang it so forcefullly, it would have "sent a message to McCartney" what he didn't like in terms of "the softer, friendly Beatles" he represented.
McCartney had soon afterwards responded with their first single, the 1964 hit "Can't buy Me Love", selling a record 2.1 million copies in the United States and more than 500,000 in Britain.
"It's the exact opposite," Mason says. "It's a soft, floppy song about how there are important things in life that money can't buy, that's what I need. It's a perfect response to "Money"."
"Not only was it an obvious response to Lennon in a very idealistic, McCartneyish way but it was false to Lennon. He didn't like it because he was always very much matter-of-fact and down to earth. One the idealist and the other the gritty realist."
Lennon's response? The hit single and title song of "A Hard Day's Night".
Mason quotes: I've been working like a dog to get you money to buy you things/and it's worth it just to hear you say you're going to give me everything...
"So the implication is I work to keep you happy," Mason says. "You're happy, therefore you love me. So, therefore, money buys you, essentially. It's the total opposite of "Can't Buy Me Love".
By Mason's account, the 1965 single, "I Feel Fine", the next song to deal with money, was "another Lennon song and he drove the nail in."
The more acerbic Beatle had done this subtly, by bringing words and images from the two earlier songs. "He actually ties together the two song, "Can't Buy Me Love" and "A Hard Day's Night". In the former, McCartney had mentioned diamond rings as the epitome of unnecessary wealth. "A Hard Day's Night" "used the word 'things'."
In "I Feel Fine", Lennon writes: ...That her baby buys her things you know/he buys her diamond rings you know...
"And, essentially," says Mason, "he closed off the dialogue. Because he had two hits in response to McCartney's one and McCartney couldn't say anything more because it was so emphatically done."
Well, almost. On the flip side of the "I Feel Fine" single, was "She's A Woman", the Beatles' first drug song, written by McCartney. "It also dealt with the money question," says Mason. He quotes its line that my love don't bring me presents. "It was so much weaker than anything Lennon had come up with in response to McCartney," Mason says.
"So McCartney was still trying to assert an anti-materialistic view. It was almost anaemic, it was such a weak and pathetic lyric. McCartney couldn't sustain the dialogue."
Mason says an analyst, such as himself, "is a person who can take apart things and put them together".
He has sought to present a different perspective of the two songwriters in his thesis. "People look at them ironically," he says. "I wanted to present a different view that looks at them as people."
Mason says he is not a collector of Beatles' recordings or "a crazy fan" - he prefers Bob Dylan - but admires their work and considers them of historic importance.
He still remembers the first time he heard "A Hard Day's Night" in 1964. That was the year the Beatles toured Australia.
He insists his work will stand out from so much of what has been written about the Fab Four. "With the Beatles as historical subjects," he says, "most people who look at them use other things as sources."
"They would look at newspaper reports, press statements, interviews but not the lyrics of their songs. My thesis, although it does incorporate all these other things, focuses fundamentally on the lyrics."