In the previous song, it is unclear who the "bone-weary traveler" is. Is it the speaker, or someone the speaker sees from his motel window and identifies with?
Here, the pronoun shifts again. In the verses, the speaker refers to a "he," some confounding person. In the verses, the song has a man speaking in first person ("I think") to his lover, Marion.
We're going to have to assume that the "he" of the verses and the "I" of the chorus are the same person, otherwise what holds the two together? The "I" becomes "he"... when other people are discussing him.
The first verse opens with a line one might hear from a teacher about a distracted student: "The boy’s got brains/ He just refuse to use ’em and that’s all." The boy’s response is a version of "ignorance is bliss": “The more I get to thinking, the less I tend to laugh.” Simon revisits this idea in the twin songs "Think to Much" on his next album.
(In a moment of lyrical weakness or laziness, Simon ends the first verse with a new rhyme-- "brains/abstains," then gives up on that couplet idea for the second and third verses.)
In the second verse, his heart beats on his right instead of his left. This is no longer just a frustrating choice that beleaguers a teacher, it is something for a scientific journal: "a strange phenomenon/ The laws of nature denied." His response this time was that it was an adaptation make in reaction to some unnamed threat: "I shifted my heart for its safety’s sake.”
He refuses to use his mind, his heart's desires are dubious, and then he employs his nice singing "voice" to be duplicitous: "his words don’t connect to his eyes."
His response is hard to parse: "when I sing/ I can hear the truth auditioning.” An "audition" is an attempt to be heard, a prelude to being allowed to act or sing before an audience. So if the truth is "auditioning," at least he is trying to convey the meaning and emotion of the song.
So here is our man, according to those who know him-- purposefully unthinking, guarded in love, and prone to hiding his feelings.
Are we all that surprised that his relationship with Marion is "in trouble"? The true surprise is that he is in a relationship altogether.
He would rather "laugh" than "think." He hides his heart. He sings (to quote "Kathy's Song) songs he "can't believe." His entire life is lived as if he wants all of his experiences to be happening to someone else. In short, he is in massive, willful denial.
So of course he doesn't "believe" Marion at first when she says that their relationship is "in trouble." He doesn't want to think about it, he never allowed himself to get that close to her... and, like all insincere people, he cannot appreciate sincerity when he hears it.
What's his assessment? That love is a "game." (Which idea stands in direct contradiction to that of the speaker of "Congratulations," who says "love is not a game.") It is predictable that a shallow person such as this would be dismissive of love.
He also concludes that the game is "easy" for "other people." Once again, he externalizes his problems. Love is just a game he is not good at, like chess.
Suddenly, something is his problem. Something real, and really bad, is happening, and it is happening to him and not someone else. Well then, at least it's no one's fault (including his own). And of course there is nothing he could do about it anyway.
"Oh, Marion," we have to say, "How did you get mixed up with this guy in the first place?"
Next Song: Ace in the Hole