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History

The Scientific Contributions of Al-Hasan Ibn al-Haytham

Quick fact

Al-Haytham conducted the first documented experiments with the camera obscura, using it to prove that light travels in straight lines and that vision results from light entering the eye—not from rays emitted by the eye.

Why this is interesting

We often credit Galileo or Newton with inventing modern science, but did you know that an 11th-century scholar from Basra, Al-Hasan Ibn al-Haytham, was among the first to insist that scientific claims must be proven through experiments?