Amnesia: The Dark Descent - Daniel's Thoughts

[Zaffre]

He's not mute. A quarter of the game is spent listening to him talk and by the end his character is well established. The reason why he doesn't speak during the game is because it breaks immersion and he never really needs to speak apart from the short Agrippa section (which was a bit immersion-breaking for not having Daniel speak actually).

I can see your point. The flashbacks do contribute to his character and development, as well as the diaries, notes, and whatnot.