Geoff's silence symbolizes the wandering of his mind to distant places in Sophie's view. This can be inferred from the context of the passage and Sophie's perception of Geoff's character.

1. Geoff's Personality:
- Throughout the passage, Geoff is described as a quiet and reserved person. He doesn't engage in conversations and often remains silent.
- Sophie perceives Geoff's personality as vague, which implies that she finds it difficult to understand him.

2. Sophie's Observations:
- Sophie notices that when Geoff is silent, his mind seems to be somewhere else, as if he is mentally wandering to distant places.
- This observation suggests that Geoff's silence is not due to a lack of interest or engagement, but rather because his thoughts are focused on something other than the current conversation or surroundings.
- Sophie sees this as a characteristic of Geoff's nature, and it influences her perception of him.

3. Contextual Clues:
- The passage mentions that Geoff often has a distant look in his eyes, further emphasizing his mental detachment from the present moment.
- Sophie's interpretation of Geoff's silence as a reflection of his mind wandering to distant places suggests that she associates his silence with a form of escapism or daydreaming.

4. Symbolism of Silence:
- In literature, silence is often used as a powerful symbol to convey various meanings.
- In this case, Geoff's silence symbolizes his disengagement from the immediate environment, as his mind is preoccupied with thoughts of far-off places.
- This symbol highlights Geoff's introspective and imaginative nature, as well as his inclination towards daydreaming and escapism.

In conclusion, Geoff's silence symbolizes the wandering of his mind to distant places in Sophie's view. Sophie observes that Geoff's silence is not a reflection of disinterest or aloofness, but rather a manifestation of his introspective and imaginative nature. This symbol adds depth to Geoff's character and influences Sophie's perception of him.