Question 1

Who was Ibn al-Haytham?

Accepted Answer

An eleventh-century scholar whose work on optics overturned the accepted theory of vision and who is described by many historians as having practised something close to the **modern scientific method** six centuries before it was formalised in Europe.

**The question he settled.** Greek theories of vision split between **emission** — the eye sends out rays that touch objects, held by Euclid and Ptolemy — and **intromission**, that something enters the eye. Ibn al-Haytham argued decisively for intromission: light travels from a source, reflects off objects, and enters the eye. **He demonstrated it experimentally** rather than arguing it philosophically, which is the significant part.

**How he worked.** His *Book of Optics* sets out hypotheses, describes experiments designed to test them, and reports the results — using the **camera obscura**, darkened rooms and controlled apertures to show how light travels in straight lines and how images form. He wrote that the seeker after truth should subject the writings of predecessors to scrutiny and doubt, including his own, which is a recognisably scientific stance.

**What else he established:** the laws of reflection and work on refraction; that light takes time to travel and slows in denser media; analysis of the anatomy of the eye and the mechanism of image formation; explanations of atmospheric refraction, twilight and why the moon appears larger near the horizon; and studies of spherical and parabolic mirrors.

**The legend.** He is said to have feigned madness to escape the consequences of a failed engineering commission to control the Nile flooding, spending years under house arrest — during which he produced much of his work. The story is told by later sources and may be embellished.

**His influence.** The *Book of Optics* was translated into Latin and shaped European work for centuries, influencing Roger Bacon, Kepler and the development of lenses and perspective in Renaissance art.

**Why he is not better known** in the West is largely an accident of historiography, which long treated the scientific revolution as beginning in Europe.

Question 2

Who was Ibn Battuta?

Accepted Answer

Ibn Battuta (1304 – c. 1369) was a Moroccan scholar and traveller whose journeys covered a distance far exceeding Marco Polo's, across some three decades — and whose account is one of the richest

Question 3

Did Eratosthenes really measure the Earth?

Accepted Answer

Yes — and the measurement was remarkably good, achieved with geometry, a well and the distance between two cities, around 240 BC. The observation he started from. In Syene — modern Aswan — at noon on

Question 4

Who was Ibn Sina, and why does he matter?

Accepted Answer

Ibn Sina (c. 980–1037), known in the Latin West as Avicenna, was a Persian polymath whose medical encyclopaedia was a standard European university textbook for six centuries — an influence few works

Question 5

Who was al-Khwarizmi and why does algorithm come from his name?

Accepted Answer

Muhammad ibn Musa al-Khwarizmi was a Persian scholar working in Baghdad in the early ninth century, and two of the most common words in mathematics and computing descend from his name and his work.

Question 6

Who was Hypatia of Alexandria?

Accepted Answer

Hypatia was a mathematician, astronomer and philosopher who taught in Alexandria around AD 400, and one of the few women scholars of the ancient world whose reputation is securely documented by

Question 7

Who was Hildegard of Bingen?

Accepted Answer

A twelfth-century German abbess, composer, writer, natural philosopher and political correspondent — one of the few medieval women whose work survives in substantial quantity, and whose range is

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