It was a fundamental principle of the Enlightenment that the nature of the human person can be adequately described without mention of social relationships. A person’s relations with others, even if important, are not essential and describe nothing that is, strictly speaking, necessary to one’s being what one is. This principle underlies all their talk about the “state of nature” and the “social contract,” and from it is derived the notion that the only obligations are those voluntarily assumed.
In the hands of an acute, but narrow, reasoner like Bentham (and an extreme nominalist into the bargain), the idea of “relation” is but a “fictitious entity,” though necessary for “convenience of discourse.” And, more specifically, he remarks that “the community is a fictitious body,” and it is but “the sum of the interests of the several members who compose it.”
That is where liberals of all stripes and conservatives part company.