I read this on Wiki..
The song is in Am, with a shift to a ♭7 (Am/G) on "all" (bass note G) and a 6 (D9 (major 3rd F#)) after "love" (bass note F#) to a ♭6 (Fmaj7) on "sleeping" (bass note F). This 8-♭7-6-♭6 progression has been described as an Aeolian/Dorian hybrid. Everett notes that the change from the minor mode verse (A-B) to the parallel major for the bridge might express hope that "unrealized potential" described in the lyrics is to be "fulfilled," but that the continued minor triads (III, VI and II) "seem to express a strong dismay that love is not to be unfolded."
Clapton's guitar contribution has been described as making this a "monumental" track; particularly notable features include the increasing lengths of thrice-heard first scale degrees (0.17-0.19), the restraint showed by rests in many bars then unexpected appearances (as at 0.28-0.29), commanding turnaround phrases (0.31-0.33), expressive string bends marking modal changes from C to C# (0.47-0.53), power retransition (1.21-1.24), emotive vibrato (2.01-2.07), and a solo (1.55-2.31) with a "measured rise in intensity, rhythmic activity, tonal drive and registral climb."
What Everett is saying is that musically the song is interesting.
There are two verses and then a Bridge, the bridge is the part where he sings 'I dont know why.......etc'
The verses are in minor key, on the bridge it changes to major key (which is interesting)
The minor key verses are a mixture of two scales (or modes) Aoelian & Dorian (which is interesting)
The minor verses are indeed sad but the brighter major bridge might express hope that the "unrealized potential" described in the verse lyrics will be fulfilled..........but that the continued minor verses "seem to express a strong dismay that love is not to be unfolded."
its an interesting theme.
also...."Clapton's guitar contribution has been described as making this a "monumental" track"
Ohh I agree with him there !
Re Kevins idea that Paul shouldve done the solo, if you read what George says in the Anthology, he specifically says that the others were not interested in the song, but when he arrived that day with Clapton and said Eric would be playing on it, everybody then became interested.