Contribution made by Avempace

Avempace (Abû Bakr Muḥammad Ibn Yaḥyà ibn aṣ-Ṣâ’igh at-Tûjîbî Ibn Bâjja al-Tujibi) born at Saragossa near the end of the eleventh century was celebrated as a physician, mathematician, astronomer and philosopher. He died in Fez in 1138.

Avempace developed the concept that there is always a reaction force for every force exerted. This theory is a precursor of Newton’s law of universal gravitation.

Avempace assumed that all motion is fundamentally regular, orderly, and consistent, which directly contradicted Aristotle’s observation that motion is a kind of change.

About 1118 he wrote at Seville, a number of logical treatises. He wrote several smaller treatises, among were Logical Tractates, a work on the soul, another on the conduct of the solitary, also on the union of the universal intellect with man, and a farewell letter; to these may be added commentaries on the Physics, Meteorology and other works of Aristotle related to physical science.

Avempace’s theory regarding the relationship between light and color marks a break with the thesis commonly held that the effect of light on a transparent medium can be produce only in so far as the latter is transparent in actuality.

For Avempace, light is already a sort of color, any effect produced by the color on the transparent medium is equivalent precisely to the actualization of this transparency as such.
Contribution made by Avempace

The Universal Law of Gravitation

The universal law of gravitation was discovered by Newton in the seventeenth century. Before Newton’s discovery, no one knew of the existence of such law.

The year was 1665; the month was August. Newton, then a 23 year old Cambridge University student retired to the solitude of his family’s farm. The university was closed for two years because of the Greta Plaque.

There is a story that Isaac Newton was inspired by the fall of an apple, to consider whether gravity was responsible for the motion of the moon as well. He was wondering what force could hold the moon in its path when the fall of an apple made him think that it might be the same of gravitational force.

With the idea of gravity fixed in his mind, Newton began the task of determining the mathematics involved in universal gravitation.

Newton himself never wrote about that day in the orchard, but he did reminisce about it to friends some 50 years later.

Newton’s realization that gravity is universal had important implications. Newton recognized that the laws of motion must also be universal in character.

Newton’s law of gravitation was the first theory to accurately describe the motion of objects on Earth as well as the planetary motion that astronomers had long observed. 

According to Newton’s universal law of gravitation ‘every particle in the universe attracts every other particle in the universe with a force that is directly proportional to the product of the masses of those particles and inversely proportional the square do the distance between those particles.

Newton’s law led to many new discoveries, the most important of which was the discovery of the planet Neptune in 1864.
The Universal Law of Gravitation