INTRODUCTION

The Islamic Golden Age was a great flowering of the sciences and arts that began in the capital of the Abbasid Caliphate, Baghdad, in the mid-8th century and lasted for about 500 years. It laid the foundations for experimentation and the modern scientific method. In the same period in Europe, however, several hundred years were to pass before scientific thought was to overcome the restrictions of religious dogma.

Dangerous thinking

For centuries, the Catholic Church’s view of the Universe was based on Aristotle’s idea that Earth was at the orbital centre of all celestial bodies. Then, in about 1532, after years of struggling with its complex mathematics, Polish physician Nicolaus Copernicus completed his heretical model of the Universe that had the Sun at its centre. Aware of the heresy, he was careful to state that it was only a mathematical model, and he waited until he was on the point of death before publishing, but the Copernican model quickly won many advocates. German astrologer Johannes Kepler refined Copernicus’s theory using observations by his Danish mentor Tycho Brahe, and calculated that the orbits of Mars and, by inference, the other planets were ellipses. Improved telescopes allowed Italian polymath Galileo Galilei to identify four moons of Jupiter in 1610. The new cosmology’s explanatory power was becoming undeniable.

  Galileo also demonstrated the power of scientific experiment, investigating the physics of falling objects and devising the pendulum as an effective timekeeper, which Dutchman Christiaan Huygens used to build the first pendulum clock in 1657. English philosopher Francis Bacon wrote two books laying out his ideas for a scientific method, and the theoretical groundwork for modern science, based on experiment, observation, and measurement, was developed.

  New discoveries followed thick and fast. Robert Boyle used an air pump to investigate the properties of air, while Huygens and English physicist Isaac Newton came up with opposing theories of how light travels, establishing the science of optics. Danish astronomer Ole Rømer noted discrepancies in the timetable of eclipses of the moons of Jupiter, and used these to calculate an approximate value for the speed of light. Rømer’s compatriot, Bishop Nicolas Steno, was sceptical of much ancient wisdom, and developed his own ideas in both anatomy and geology. He laid down the principles of stratigraphy (the study of rock layers), establishing a new scientific basis for geology.

Micro-worlds

Throughout the 17th century, developments in technology drove scientific discovery at the smallest scale. In the early 1600s, Dutch spectacle-makers developed the first microscopes, and, later that century, Robert Hooke built his own and made beautiful drawings of his findings, revealing the intricate structure of tiny bugs such as fleas for the first time. Dutch draper Antonie van Leeuwenhoek, perhaps inspired by Hooke’s drawings, made hundreds of his own microscopes and found tiny life forms in places where no one had thought of looking before, such as water. Leeuwenhoek had discovered single-celled life forms such as protists and bacteria, which he called “animalcules”. When he reported his findings to the British Royal Society, they sent three priests to certify that he had really seen such things. Dutch microscopist Jan Swammerdam showed that egg, larva, pupa, and adult are all stages in the development of an insect, and not separate animals created by God. Old ideas dating back to Aristotle were swept away by these new discoveries. Meanwhile, English biologist John Ray compiled an enormous encyclopaedia of plants, which marked the first serious attempt at systematic classification.

Mathematical analysis

Heralding the Enlightenment, these discoveries laid the groundwork for the modern scientific disciplines of astronomy, chemistry, geology, physics, and biology. The century’s crowning achievement came with Newton’s treatise Philosophiæ Naturalis Principia Mathematica, which laid out his laws of motion and gravity. Newtonian physics was to remain the best description of the physical world for more than two centuries, and together with the analytical techniques of calculus developed independently by Newton and Gottfried Wilhelm Leibniz, it would provide a powerful tool for future scientific study.