[henry quirk]

Classic, we're talking about two vastly different kinds of creatures here.

My expectations of one are not translatable to the other.

On one hand: we have the human individual for who it is natural to speak.

On the other: we have the dog for which it is natural not to speak.

As to the damaged human individual who cannot speak, whether or not such a person is capable of love depends entirely on the nature of the damage.

If I am stricken with throat cancer and lose my voice: I can still love.

If I were born with a damaged brain that limited my ability to speak as one aspect of the damage, then, it's entirely possible I would be unable to love.

Your question is awfully broad. Care to narrow it a bit?

Again: what makes human love unique is that it is 'done' within an 'I'. There is deliberation and reflection. That we communicate ourselves, transmit ourselves, through speech is the tool of the 'I', but not the definer of 'I'.