Did al-Ghazali kill science?

A well-known story says that science flourished in the early Muslim world until the theologian Abu Hamid al-Ghazali (c. 1056–1111) turned people against philosophy and reason, after which it declined. The story took shape in 19th-century European scholarship, especially Ernest Renan's, and has been repeated more recently by the physicist Pervez Hoodbhoy, the Nobel Prize-winning physicist Steven Weinberg and the science communicator Neil deGrasse Tyson, who said al-Ghazali called working with numbers “the work of the devil”.

The paper separates two claims: that al-Ghazali rejected philosophy and the sciences, and that his influence caused their decline. To test the first, it reads three of his books closely: The Incoherence of the Philosophers, Deliverance from Error and The Book of Knowledge. His target was a set of metaphysical teachings of al-Farabi and Ibn Sina, such as the eternity of the world, and their claim to have proved them with the certainty of mathematics. Mathematics itself he accepted as rigorous proof. He even warned that a believer who denies proven facts, such as the calculation of eclipses, harms religion. He used logic extensively, and he counted medicine and mathematics as a communal obligation (fard kifaya): a community must have people skilled in them.

His famous example of fire and cotton is often read as a denial of natural law. Drawing on the historian Frank Griffel, the authors argue that al-Ghazali denied only that fire burns cotton by a necessity independent of God, not that it normally does or that this can be studied. On the second claim, they point to George Saliba's history of astronomy: the Maragha tradition and Ibn al-Shatir produced major innovations centuries after al-Ghazali. Philosophy also continued under new names, inside kalam (Islamic theology) and in thinkers such as Fakhr al-Din al-Razi.

The authors do not make al-Ghazali a modern secular rationalist: he placed revelation above human reasoning and opposed key philosophical doctrines. But they conclude that his legacy was transformation, not termination. Explaining later changes in Muslim science means looking at patronage, institutions, economics and politics across many regions, not blaming one theologian.