Answer by Christopher Reiss:
Silence.
Michael Corleone (Character) from The Godfather (1972)
Stealth intellect has a slack expression, does not react, does not laugh, does not challenge, does not question.
It sits quietly, like a coiled snake, soaking up everyone and everything, until it makes a sudden move at the time of its choosing. You don't want to be in the path of that strike.
AB's Reflections 