Truth does not contradict truth

The Decisive Treatise: the harmony of religion and philosophy

Averroes 1126 · 1198Truth cannot contradict truth: philosophy and faith agree.

What it claims

A demonstration never truly contradicts the Law. When it contradicts the apparent meaning of a text, that apparent meaning is not the true meaning: it must be interpreted, according to the rules of the Arabic language.

Why

Two truths cannot contradict each other: if the Law and demonstration seem to clash, the text has a meaning other than the apparent one.

The same idea through history

Averroes1179The version presented here, written by a Muslim judge for Muslims, some time after al-Ghazali's attacks on the philosophers.

Thomas Aquinas1260Thomas Aquinas states the same rule in the Summa contra Gentiles (c. 1259-1265). He did not know the Decisive Treatise, which was not translated into Latin in the Middle Ages, and he elsewhere fights the Paris "Averroists".

In short

"Truth does not contradict truth" is an argument by Averroes (The Decisive Treatise, §3-14 (1179), 1179) on the question "Should we believe without proof?" (answer: faith and reason agree). Its claim: A demonstration never truly contradicts the Law. When it contradicts the apparent meaning of a text, that apparent meaning is not the true meaning: it must be interpreted, according to the rules of the Arabic language. According to AskPhilosophy's logic check (Z3 solver), the conclusion does follow from its 4 premises. AskPhilosophy presents 3 objections, 3 of them with a documented reply, and the original text behind each premise, checked word for word.

The Decisive Treatise, §3-14 (1179)

Valid

In the 12th century, in al-Andalus, Greek philosophy is suspect: al-Ghazali has accused the philosophers of unbelief. Averroes is a judge (qadi), and he answers as a jurist. First, the Qur'an commands us to reflect on the universe through reason, and the best way of reasoning is demonstration: so studying philosophy, even in the books of the Ancients who were not Muslims, is a duty for those capable of it. Next, can this philosophy contradict religion? No, he answers, and here is why.

click a premise to reject it

If you accept every premise, logic forces you to accept the conclusion. So the debate is about the premises.

Checked by a logic solver: the premises cannot all be true while the conclusion is false.

Valid, with no hidden premise. If the Law is true (P1) and so is the demonstration (P2), they cannot contradict each other (P3): a disagreement can only come from too literal a reading of the text. All the weight rests on two premises. P1: an unbeliever does not grant it, but Averroes writes as a judge, for Muslims. P2: what is called a "demonstration" must really be one. That is where al-Ghazali attacks: in his view, the philosophers demonstrate nothing of what they claim about God and the world.

Analogy. A reliable witness and a sharp photo show the same scene. If the witness seems to say something other than the photo, you throw out neither: you ask whether you understood their words, perhaps a figure of speech. But you must be sure the photo is sharp: that is the question of P2.

Objections

Each objection is a conversation: click to see who replies and where the debate stands.

Objection anticipated by Averroes attacks the conclusion

Muslims unanimously take certain texts in their apparent meaning. If a demonstration forces us to interpret them otherwise, we break the unanimous agreement of the community (ijma'), and whoever breaks it may be accused of unbelief.

Averroès replies

Averroès

If unanimous agreement were established with certainty, one could not interpret against it; but if it is only presumed, one can. Now on questions of doctrine it can never be established with certainty: one would have to know all the scholars of a period and each one's view, and be sure that none of them held that some meanings must stay reserved for scholars. Yet many, from the first days of Islam, held exactly that.

The debate goes on (our summary) The answer protects the scholar who interprets, and here Averroes relies on al-Ghazali himself, who held that one cannot declare with certainty an unbeliever someone who departs from consensus in this kind of interpretation. But Averroes keeps limits: on the principles of religion (God, prophecy, the future life), denying the text's meaning is unbelief; and he forbids divulging learned interpretations to the masses.

Al-Ghazali 1095 · attacks premise 2

The philosophers claim to demonstrate, but in their metaphysics they respect none of the conditions of demonstration that they themselves laid down in their logic. Their "demonstrations" about God and the world are no better than opinions. And on three points (the eternal world, a God who would not know particular things, the denial of bodily resurrection), they contradict religion: they must be declared unbelievers.

Averroès replies

Averroès

On the three points, al-Ghazali is wrong about the philosophers. For them, the life after death is a question for inquiry. They do not say that God is ignorant of particular things. And what they call "the eternity of the world" does not have the meaning for which the theologians accuse them of unbelief.

The debate goes on (our summary) On demonstration, Averroes grants part of the charge: he himself judges that, on some points, what Avicenna and other philosophers of Islam established is only opinion, and that the true demonstrations are in Aristotle. So the question stays open for P2: who decides what is truly demonstrated? A critic will say the argument assumes we can always recognise a demonstration.

The opponents of "Latin Averroism" (Paris, 13th century) 1277 · attacks premise 3

Paris masters, readers of Averroes, teach that reason necessarily concludes things that faith denies, for instance that the world is eternal. This amounts to saying that something can be true according to philosophy and false according to faith: two contrary truths. And if scholars have a hidden meaning and the masses the apparent one, is that not already two truths, one for each audience?

Averroès replies

summary: their text is not yet in our corpus

Averroès Averroes' answer in advance

There are not two truths, but one truth and its images. For the things that only demonstration makes known, God gave images and symbols to those who have no access to demonstration. That is why the Law has an apparent and an inner meaning: the apparent meaning is these images; the inner meaning is the realities they stand for, which are clear only to the people of demonstration.

The debate goes on (our summary) In 1277 the bishop of Paris condemned masters who allegedly said things were true "according to philosophy, but not according to the Catholic faith, as if there were two contrary truths". No text of Averroes holds this thesis, and historians doubt that Siger of Brabant held it in that form. Yet a difficulty remains: Averroes asks the masses to believe the apparent meaning and forbids revealing the interpretations to them. His critics see in this a double language, if not a double truth.