With the conclusion of Theorem, Pasolini left us in the company of today's bourgeois paterfamilias, stripped of all save his despairing confusion, wandering distractedly across the acid volcanic wastes that had been glimpsed previously throughout the film like almost subliminal reminders of his cryptozoic ancestry. As if resuming the tale, Pigsty [or Pigpen] … begins in the same setting, with an identical outcast struggling across the lifeless ash-dunes; the pangs assailing him now, however, are no longer those of conscience or doubt but simply those of an excruciating hunger. Pasolini gives us no time to consider this apparent simplification before he has once again broadened the metaphor alarmingly by cutting in the first glimpses of the parallel story of which the film is composed. In direct balance to Theorem …, Pigsty punctuates the primitive with the ornate; although this time the two separate narratives are of roughly equal length, if not of equivalent complexity….

Pigsty continues to chart the course of Pasolini's detachment from the ideology of his Accattone days….

Pigsty, like Theorem, draws both comfort and despair from the gratified hungers of humanity, blames no one for their actions or their inactions, and ultimately adopts a fatalistic standpoint (the connection with Edipo Re is hinted enigmatically by the cannibal's final words) which concludes that other forces than man's are behind all that he attempts to do. (p. 99)

The wilful interlocking of two utterly different narratives has its own strange ambiguity. It can be argued that the exercise is meaningless, yet the results never are. The contrasts and clashes between [Willard Maas's] Orgia and Porcile set up disturbing, often indefinable echoes…. Since we know far more about the porcophile Julian than we do about the cannibal, the relationship between them is difficult to determine—particularly as the former is hardly as anti-social as the latter. But relationship there undoubtedly is, in their passion, in their detachment, and finally in their deaths.

Originally, Pasolini had planned that Julian would be visited by the ghost of Spinoza, assuring him that his love for the pigs is equivalent to a belief in God; this splendidly ambivalent interpolation is gone, but the sense of the self-destructive nature of any dedication remains, the theological aspects being brought out more by the cannibal's ceremonial disposal of heads in the marvellously gaping mouth of the volcano and his condemnation at the hands of some dishevelled clerics than by Julian's more amiable martyrdom. (pp. 99-100)

If one can conclude anything from the film, it is that Pasolini has transcended the efforts of any of his contemporaries to define the Italian dilemma in both poetic and cinematic terms. (p. 100)