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the program. Hello in the collection of Cambridge University Library is a modest

notebook which belongs to Isaac Newton when he was a student.

As well as notes about the mathematical textbooks he was reading, it contains the detail of some of his earliest experiments.

One of these, which would horrify modern researchers,

entail inserting a knitting needle behind his eyeball to see what effect this had on his vision.

Newton's dangerous experiments were part of a two and a half thousand year quest to

understand the nature of human vision. Ancient thinkers were fascinated by the

eye, believing it contained a mysterious illuminating fire. In later centuries it became known in Leonardo's famous phrase as

the window of the soul, but establishing the structures and properties of the eye

took many centuries on the work of some of the greatest figures of Western thought.

With me to discuss the history of the I are Patricia Farrah, senior tutor of Claire College,

University of Cambridge, William Aleph, Gresham Professor of Physic at Gresham College, and Robert Ilyph, Professor

of Intellectual History and the History of Science at the University of Sussex.

Perusha Farrah, who were the earliest thinkers to study the workings of the other that we know about?

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