Kuzari

The Kuzari, full title The Book of Refutation and Proof in Support of the Abased Religion (Arabic: كتاب الحجة و الدليل في نصرة الدين الذليل‎‎), also known as the Book of the Kuzari, (Hebrew: ספר הכוזרי‎) is one of the most famous works of the medieval Spanish Jewish philosopher and poet Judah Halevi, completed around 1140. It is regarded as one the most important apologetic works of Jewish philosophy.

Divided into five parts ("ma'amarim" – articles), it takes the form of a dialogue between a rabbi and a pagan. The pagan is then mythologized as the king of the Khazars who has invited the rabbi to instruct him in the tenets of Judaism. Originally written in Arabic, the book was translated by numerous scholars, including Judah ben Saul ibn Tibbon, into Hebrew and other languages. The question whether Halevi's work had any historical basis regarding the Khazars conversion to Judaism is controversial among scholars.

After a short account of the incidents preceding the conversion of the king, and of his conversations with a philosopher, a Christian, and a Muslim concerning their respective beliefs, a Jew appears on the stage, and by his first statement startles the king; for, instead of giving him proofs of the existence of God, he asserts and explains the miracles performed by Him in favor of the Israelites.

The king expresses his astonishment at this exordium, which seems to him incoherent; but the Jew replies that the existence of God, the creation of the world, etc., being taught by religion, do not need any speculative demonstrations. Further, he propounds the principle upon which his religious system is founded; namely, that revealed religion is far superior to natural religion. For the aim of ethical training, which is the object of religion, is not to create in man good intentions, but to cause him to perform good deeds. This aim can not be attained by philosophy, which is undecided as to the nature of good, but can be secured by religious training, which teaches what is good. As science is the sum of all truth found by successive generations, so religious training is based upon a set of traditions; in other words, history is an important factor in the development of human culture and science.

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