For Boromir the focus of life is unitary, one pointed. Boromir places faith in powerful objects. Boromir is drawn to single objects which have a singular power. This seems to resonate with Boromir’s singular obsession of being the redeeming son of Gondor.

Top Boromir and the ring and above Narsil.

Boromir is drawn obsessively to talismans of power. We sense these objects resonate not with his hope of saving his people but his own deep sense of aloneness.

At the council of Elrond the ‘singularity’ of Boromir is reflected in his ‘one idea’ to wield the ring. He won’t be dissuaded.
See above how Boromir’s gesture at the council mirrors the action of Isildur in taking the one ring.

The Hobbit’s delight in Boromir’s swordplay. There is a growing attachment in Boromir to the two hobbits. Fun with Merry and Pippin distract Boromir from his singular obsession. The pleasure taken in Merry and Pippin partially lifts the shadow. Boromir can be a boy again. For once we see how Boromir can embrace life directly.

The pleasure of the hobbits is reflected back by Boromir

At his death Boromir enquires after the ‘little ones,’ Merry and Pippin. Boromir has been obsessed by the one ring and it’s singular power. At Amon Hen he lost himself again in his obsession. When Boromir speaks of ‘the little ones’ we see his depth of care for the two hobbits. Boromir has redeemed his singular obsession. He has moved from obsession with the one ring ,the ‘little thing,’ to care and compassion for the two hobbits, for ‘the little ones.’