Along many dimensions, human nature and human situations are so positioned that when the individual's relations begin to exceed a certain extensiveness, he becomes all the more thrown back upon himself. This is not only a matter of the quantitative extension of the circle, which must inevitably reduce the personal interestedness in it of each of its points down to a minimum; it is also a matter of qualitative diversification within the circle that impeded the focusing of interest upon any one point, and which thus leaves egoism as the logical outcome of the general paralysis of irreconcilable demands.

XREF: Connects to Simmel's broader urban sociology — the metropolis intensifies individuality and psychological withdrawal precisely because of its scale and diversity, a paradox worth recalling.

Georg Simmel, on individuality and social…, loc. 699