Al-Sadr's criticism...

Al-Sadr's criticism, however, is addressed mainly to Kant's denial of the possibility of metaphysics. According to Kant, there can be no synthetic judgements relating to metaphysics. Empirical synthetic judgements, like that of the sciences, involve mind's formal modes and categories: space and time and the categories of quantity, quality, relation and modality. These finite categories apply to sense-experience and phenomena, not to things-in-themselves, the noumenal.

God, soul, and the noumenal world lie beyond experience, and hence there can be no empirical synthetic judgements about them. Also, since the noumenal world transcends mind's a priori concepts, a priori synthetic judgements, like that of logic and mathematics, which are purely formal and empty of content, cannot pertain to metaphysics. Accordingly there is no room in metaphysics for anything but analytic judgements, which do not constitute any real knowledge at all.

Al-Sadr, it seems, does not notice that Kant has built the realm of the mind and experience into an almost autonomous and self-contained world by itself (almost, we said, allowing for Kant's inconsequential belief in the unknowable things-in-themselves, which cause sensations). This is shown by the 'two basic errors' in Kant's theory that he points out.

Firstly, he points out, Kant considers mathematical science to 'produce' mathematical truths and principles, which are above error and contradiction, whereas every realistic philosophy must recognize that science does not 'produce' or 'create' truths. Science is revelatory of what transcends the limits of mind. The propositions of mathematics reflect an objective reality and are, in this sense, similar to the laws of natural science.

Secondly, "Kant considers the laws that have their foundation in the human mind as laws of the mind, and not scientific reflections of the objective laws that govern and regulate the world as a whole. They are nothing but relations present in the mind naturally, and used by the mind to organize its empirical knowledge." Such a position, al-Sadr says, leads to idealism, "for if the primary knowledge in the mind'.

Is nothing but dependent relations awaiting a subject in which to appear, then how could we move from conception to objectivity? Further, how could- we prove the objective reality of our various sense perceptions that is, the natural phenomena whose objectivity Kant admits?" The fact is that Kant's position is already deeply steeped in idealism.