'Yesterday'

'Yesterday': there's a simple correlative between the mood of the song and the cadence the melody line, or more specifically is rising or falling. The very simplicity of this, as a composer's device, enables its genuine affect.

So, the opening 'yesterday' falls away, at its end; but then recalling his former happiness ('all my troubles seemed so far away') the melody rises, to fall back down ('now they look as though they're here to stay'): down ('oh I') on the snag of his own misery but, a qualified rise ('believe') followed by a new inflection of the title subject: not the actuality of yesterday, but his belief in yesterday: the rising melody-line on the second yesterday inverts and contrasts the actuality of misery with the hopefulness entailed by belief.