The third person narrative, told entirely through the perspective of Strether, dramatizes the changes in his consciousness wrought by the atmosphere of the city of Paris. Yet, he does not bring nothing to the alchemical experiment; he carries a sense of advancing age and professional failure, a sense that is old with him, true, but also young enough for its modification, and, even, transformation. For in Chad, Strether sees a younger self that he never had. I use "had" deliberately. The fine women Strether encounters in Paris are described with deep admiration, but the handsome young man receives the only extended description of physical person. Arriving at Chad's house, Strether saw another young man smoking on the third floor balcony:
He was young too then, the gentleman up there--he was very young; young enough apparently to be amused at an elderly watcher, to be curious even to see what the elderly watcher would do on finding himself watched. There was youth in that, there was youth in the surrender to the balcony, there was youth for Strether at his moment in everything but his own business; and Chad's thus pronounced association with youth had given the next instant an extraordinary quick lift to the issue. The balcony, the distinguished front testified suddenly, for Strether's fancy, to something that was up and up; they placed the whole case materially and as by an admirable image, on a level that he found himself at the end of another moment rejoicing to think he might reach. The young man looked at him still, he looked at the young man; and the issue, by a rapid process, was that this knowledge of a perched privacy appeared to him the last of luxuries. To him too the perched privacy was open, and he saw it now but in one light--that of the only domicile, the only fireside, in the great ironic city, on which he had the shadow of a claim.
I find this passage extremely moving in its contrast of youth and age, its double seeing, its longing for transcendence and domicile ("perched privacy"), and its tenuous claim of belonging in a great ironic city. The style may be impressionistic--seeing the balcony in one light which may, and will, rapidly change to another--but it is also profoundly human.