Why does Winston feel that the man sitting next to him in the cafeteria is "not a real human but some kind of dummy?This is in chapter five pg 48

Winston Smith’s observation – that the man sitting near
him “was not a real human being but some kind of dummy” – takes place during lunch in
the canteen of the Ministry of Truth. Winston has just finished listening to a lecture
on the destruction of words from the Newspeak expert Syme. The ‘anti-philologist’ –
literally a ‘hater of words’ – ends his paean to the linguistic narrowing of thought
with the remark that “[political] Orthodoxy means not thinking – not needing to think.
Orthodoxy is unconsciousness”. The Party man sitting near Winston, loudly parroting the
principles of Ingsoc, eyeless because the light is reflecting off his spectacles, is a
kind of convenient model for Syme’s stated end of political orthodoxy.