Winston makes the statement,
if there was hope, it lay in the Proles several times. He then follows it by stating, when you put it in to words it sounded reasonable; it was when you looked at the human beings passing you on the pavement that it became an act of faith.
He then has the idea of asking an older man about his memories and whether the past was better than the present.
If Winston is putting his hope in the proles and this old man's memories, based on what he finds out from the old man, what reasons are justification for him saying it would be an act of faith?