I don't mind him not talking so much, because you can hear his voice in your heart; the same way you can hear a song in your head even if there isn't a radio playing; the same way you can hear those blackbirds flying when they're not in the sky
I imagine a soul is a little perfect crystal egg floating in your chest. Somewhere deeper than where they put your heart. Somewhere so deep inside that the doctors can't find it with all their machines and microcameras.