It becomes clear that Durkheim advances to a deeper level of argumentation, grounded in the sociological premise that the individual cannot exist in isolation from society. Viewed in isolation, the individual is a mere abstraction; in reality, it is only the social whole that truly exists. An individual who rejects the morality of their time—who denies that morality has any foundation—is therefore in effect denying society itself, placing themselves as though outside it. Durkheim meets this position with three distinct, if not entirely consistent, arguments:

First, as we have established, it is impossible to live outside society. The question is not whether one can exist independently of society, but rather in which society one wishes to live. ¹.
Alternatively, to reject society is to express a wish to die; thus Durkheim adds: It remains to be examined whether man should deny himself; the question is legitimate, but will not be examined. It will be assumed that we are right to want to live ².
Or, finally, it amounts to wanting to cease being human: We cannot get out of society without losing our humanity [...] We can only renounce it by renouncing ourselves ³.

We may note that moral sociologism does offer a foundation for morality (namely, society, and the social conditions that give rise to a given rule). That foundation, however, is relative: a moral rule justified today may no longer be justified tomorrow if social conditions change and its basis disappears, at which point it would have to be abandoned. No rule, then, is grounded in an absolute sense. What is striking about this doctrine is the way it reconciles objectivism with relativism—two positions we might ordinarily regard as incompatible.

There is, however, a persistent ambiguity in Durkheim's approach. He claims not to judge the morality of a given time but only to explain it, yet he simultaneously proposes a foundation for it.
This ambiguity is reflected in the two concepts Durkheim uses to evaluate a moral rule: the 'normal' and the 'pathological'. By deliberately avoiding the concept of 'value'—which would expose his intent to judge morality rather than merely explain it—he asks not whether a moral rule has inherent worth but whether it is 'normal' or 'pathological'. A pathological rule is one that persists despite the disappearance of the social cause that once justified it; a normal rule is one that corresponds to, or is generated by, the social state of its time.

Chapter III of The Rules of Sociological Method is largely devoted to the rhetorical task of assessing a phenomenon's worth without explicitly invoking the concept of 'value'. The notion of 'normality' enables this sleight of hand: it sidesteps direct appeal to 'value' while covertly permitting an implicit judgement of a phenomenon's worth.
Stripped of any value connotation, 'being normal' means no more than 'being frequent'. This is precisely Durkheim's interpretation of the term. Yet in refusing any evaluative dimension to normality, he runs into unresolved paradoxes—most notably the claim that crime is normal in society. All he is really saying is that crime is frequent; for him, 'normal' signifies nothing beyond the frequent (or the general, relative to a given species). The paradox arises because normality remains intrinsically bound up with value, despite Durkheim's efforts to keep the two apart.

A defining feature of moral sociologism is its attempt to avoid overt value judgements while quietly reintroducing them through concepts such as 'normality' and 'pathology' (one might also note the term 'reactionary', which, beneath an ostensibly objective description—someone adhering to rules whose conditions have disappeared—carries an implicit value judgement). Moral sociologism is thus characterised both by the adoption of multiple axiological positions and by a sustained effort to conceal them.

It is precisely this evasion of the concept of value that appears to prevent moral sociologism from establishing a genuine foundation for morality. Like Nietzsche, sociologism seems only to uncover the origin of morality, tracing moral rules back to specific social conditions. But for these rules to make a claim on us—that is, to ground morality itself—it would be necessary to show that they possess intrinsic value, and not merely that they have conditions.
It would also require showing that those social conditions themselves hold value. Durkheim demonstrates that certain moralities are necessary for the survival of particular societies. But what would he say to the immoralist who argues that what has value is precisely the dissolution of that society (or of society in general), or that society has no value, and therefore neither does morality? Durkheim shows that individualism is unworkable, that individuals cannot exist apart from society. Yet even granting this contested premise, what reply is available to someone who maintains that the individual is indeed an impossibility, a mere illusion, but that the illusory or the impossible is of greater value than the real?

It is clear that moral sociologism rests on a series of unproven value judgements—something Durkheim implicitly acknowledges when he presents one of them as a postulate: It remains to be examined whether man should deny himself [by leaving society]; the question is legitimate, but it will not be examined. We will postulate that we are right to want to live ⁴.
A foundation for morality cannot be built on a series of ungrounded value judgements; at best, these amount to no more than opinions about morality. The failure of moral sociologism thus stands as yet another illustration—following Nietzsche—of the impossibility of deriving a moral foundation from its origin, in this case a social one.

1. Sociology and philosophy, chap. II
2. Ibid.
3. Ibid.
4. Ibid.