Between about 1011 and 1021, the scholar Ibn al-Haytham (Latinised Alhazen) wrote the seven-volume Kitab al-Manazir, or Book of Optics, much of it reportedly while under house arrest in Cairo. He established that vision works by light reflecting from objects into the eye, rather than by rays issuing from it, and tested his claims with controlled experiments using apertures, lenses and the camera obscura. The work fused geometry, physics, anatomy and psychology, and is widely credited with founding the experimental scientific method. Translated into Latin around 1270, it shaped European optics, perspective and the science of vision for centuries.
The Book of Optics put understanding of light, vision and perspective on an experimental footing, later underpinning the linear perspective that transformed how Renaissance architects and planners drew and conceived urban space. It stands as a landmark of the rigorous, evidence-led method that would shape modern science.
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