Question

Arthur stood before the hearth, his fingers tracing the familiar, worn mahogany of the mantlepiece. For thirty years, the clock above it had chimed with a brassy, reassuring monotony, anchoring him to a version of himself he had long ceased to question. Outside, the city had rewritten its skyline, replacing the low brick chimneys of his youth with towers of steel and glass that caught the cold morning light. Arthur’s daughter had urged him to sell, to move to a flat where the plumbing did not rattle like a dying engine and the draughts did not seep through the floorboards. But to leave would be to admit that the tide of time had finally reached his doorstep. He adjusted the brass pendulum, a weekly ritual that felt less like maintenance and more like an act of defiance against the forward march of the streets outside. He knew every scratch on the floorboards, every water-stain on the ceiling; they were the physical ledger of his endurance. To step across the threshold into the bright, featureless modern world was to invite a dissolution of the self. So he remained, winding the clock, listening to the familiar gears grind, convinced that as long as the pendulum swung, the world outside could be kept at bay.

In the passage, the narrator's description of Arthur's interaction with the clock primarily serves to emphasize which of the following aspects of his character?