Kant, having rejected the cosmological, ontological, and design proofs, argued in the Critique of Practical Reason (1788) that the existence of God, though not directly provable, is a necessary postulate of the moral life.
The view, that matter uniquely determines the field, was a necessary postulate of an opposing ontological standpoint, according to Weyl.
Since different things were each the all, the self, and divine, it became logically necessary to postulate an unmanifest source or cause of the Yogic experience of absorption.
Philosophers have often found it necessary to postulate either abstract objects or universals.
Nevertheless it is necessary to postulate an enhanced degradation rate or increased volume of distribution, to explain this finding.
To defend compositionality along these lines it is by mo means necessary to postulate a variable in the logical form of the sentence; cf. Szabó (2010) 26.
Like Leucippus and Democritus, Epicurus felt it necessary to postulate the existence of physical atoms, but to avoid Aristotle's strictures he proposed that these should not be themselves conceptually indivisible, but should contain conceptually indivisible parts.
If a natural theory of truth like T PA) below is added, however, it is no longer necessary to postulate the global reflection principle explicitly, as theories like T PA) prove already the global reflection principle for PA.
To this ingenious suggestion, The Manual of Reason replies (TSD 66k) that it is superfluous, for "since it is possible for the relation [between meaning-relata] to be apprehended as what is signified by the sentence [as a whole], it is not necessary to postulate a semantic power with reference to the relation".
