…logic can no longer be regarded as a normative instrument whose observance guarantees freedom from error; for once propositions are produced that can be known by means other than their approved avenues, this “instrument” is incapable of weighing them. The majority of these logicians therefore brand as false anything for which their own syllogism provides no proof—a stance that is the height of ignorance, all the more so when what they reject are the reports of the prophets. Such people are included among those of whom Allah says, “Rather, they denied that of which they had no comprehensive knowledge and whose final outcome had not yet reached them” (Q 10:39).

Their attitude resembles that of an astrologer who dismisses the science of medicine, or a physician who mocks the science of astronomy. Human beings are foes to what they do not know; whoever is ignorant of something instinctively opposes it.

If the noblest forms of knowledge cannot be accessed by their method, two consequences follow. First, they have no proof for declaring false whatever lies outside their syllogism. Second, what they do know is trifling compared with what they ignore—let alone the fact that their learning brings neither salvation nor true felicity.

Eleventh Consideration: The invalidity of their assertion that the demonstrative, the rhetorical, and the dialectical methods are what the Almighty refers to in His words, “Call to the way of your Lord with wisdom…” (Q 16:125).

Eleventh Consideration (continued): They label as non-knowledge that which is in fact true and must be believed, while treating as knowledge what is actually false. In their scheme the kinds of syllogism, with respect to their matter, are five: burhān (demonstration), khuṭāba (rhetoric), jadal (dialectic), shiʿr (poetry), and safsaṭa (sophistry), the last deriving from the Greek sophistīkā. The other branches of logic likewise carry Greek names—lengthy terms such as katīghorīyās (categories), analytikā, and the like. By contrast, the Arabic language is shorter and clearer, therefore more perfect in expression and more concise in wording.

They also divide the syllogism, in respect to its form, into two kinds: the iqtirānī (categorical) and the istithnāʾī (conditional). The first is composed of categorical propositions, while the second is composed of connected or disjunctive conditionals. Before treating the syllogism itself they devote a discussion to propositions and their various types.