Lennon Or McCartney ???

This

It would be John, since he DID start the band. The two were equally responsible for their success. And Brian Epstein is responsible for the mania.

Easiest question on planet Earth. Even easier than Connery or Brosnan, Roth or Hagar, Angelina Jolie or Oprah.

Folks on this thread are saying this is a tough one. Let me educate you.

ONE:
John Lennon - 98 songs written for Beatles
Paul McCartney - 65 songs written for The Beatles

OK, so numbers alone show that John was the more important member. (The Lennon/McCartney writing credit was inaccurate. The boys did write songs together, but only about eight times. The rest of the Lennon/McCartney songs were actually written by one or the other. You really think John had anything to do with "Blackbird" or Paul had anything to do with "Julia"?) John wrote 98 songs, Paul only 65. John wrote a full 33% more Beatle songs than Paul! That alone makes John the more important Beatle.

TWO:
It was John's band! He formed it. Without John Lennon there would be no Beatles. Uhh, don't you think that makes him more important than Paul?

THREE:
At the most critical moment of the band's career (A HARD DAY'S NIGHT), John took over. Let me explain. 1963 Beatles were breaking big, however they were still a fledgling band and one of many beat groups. At this point they were afforded the opportunity to separate themselves forever from the rest of the pack (Herman's Hermits, Jerry and the Pacemakers, Dave Clark Five...) due to the fact that they were about to film a major motion picture. Now with this film about a day in the band's life they could have gone the way of The Spice Girls or they could have knocked it out of the park and become the biggest thing on Earth. Critical moment in the band's career. Strong songs in the new film will insure success and greatness. So what did the band do? They put it in the hands of John Lennon. Of the nine songs heard in the film A HARD DAY'S NIGHT, John was responsible for seven of them! (On the "Hard Day's Night" album of 13 songs, ten of them were John songs!) The group knew exactly who the most important Beatle was and at the most critical moment in their careers, they relied on John to  do all the heavy lifting.  

I prefer the "John" songs, but think they both needed each other to temper some of their more pedestrian impulses...I think Macca solo is terrible and John solo is unfocused..They needed one another to produce their best work...Too bad they didn't go on vacation for a few years, away from the band and figure this fact out...Might have stuck together a bit longer...

Just curious how you know how many songs each contributed when they're all credited to both?

I have to agree with Wesley Crusher's comments but as solo artists I always preferred Paul's solo albums and albums with Wings than any of the other members.

Yes.

However, most critics and music fans agree that the greatest rock and roll album ever made is John's first solo album, "Plastic Ono Band." That album is actually better than any Beatle album and a million miles above any Paul solo album. Heck, even George released a solo album ("All Things Must Pass") that is miles above any of Paul's best solo albums.

Having said that, on the whole Paul's solo work is far better than John's (or George's). John hit it out of the park once. Paul actually was consistently good for many solo albums.
"Band On The Run"
"Venus and Mars"
"Wings At The Speed Of Sound" 
"Wings Over America"
"Tug Of War"
Those are all amazingly good albums.