While he was more open to the influx of all these novel ideas and problems, he was less able to deal with and dispose of them.
So the professor, while encouraged by the observation of his apparent progress in the direction of human feeling and emotional warmth, was concerned to find him falling off in recuperative power.
Sophie was largely to blame for it.

Bressant was getting to depend too much upon her society.

He brightened when she came in, and was gloomy when she went out.

He liked to talk and argue with her; to dash waves of logic, impetuous but subtle, against the rock of her pure intuitions and steady consistency.

He was careful not to go too far; though, indeed, she usually had the best of the encounter.