Seeing is believing and, for scientist Ibn al-Haytham, this wasn’t just true but practically a mantra to live by. Best known for his work, the Book of Optics, al-Haytham studied the way light travelled to the eye to better understand how vision worked. And he was a big believer in experimentation. It wasn’t enough for him to theorise, he had to see it in action.

Of course, he couldn’t just be good at one thing. He had to be good at all of the things. While around 50 of his texts survive, it’s thought that he wrote 96 (though possibly more) and around half of these were on mathematics. He also studied astronomy, with a focus on the physical structure of the Earth and the movement of the planets.

A key figure of the Islamic Golden Age, al-Haytham’s work had a huge impact on many great thinkers who followed him and his experimentation meant that he was a supporter of the scientific method, long before it became the norm for Renaissance scientists.

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