Then natural philosophers began to propose earthly sources such as a rock or mountain.

Many philosophers began to discuss the church, government, education and human rights in different ways.

So the philosopher begins his search for some conceivable agreed ways of adjudicating these tangled controversial issues.

The philosopher, encouraged by his near-success, began concocting the same medicine once more.

During this period of reflection many existential philosophers began considering life-and-death issues.

In the early 19th century, scientists and philosophers across Europe began studying the nature and interaction of colors.

God had become just another being, like the host of other objects that scientists and philosophers were beginning to explore in the West.

He popularised philosophy, and many other great philosophers of the day were beginning to take him seriously.

He was the ultimate polymath when "natural philosophers" had not yet begun to specialize.

Scientists and philosophers began to question the teleological understanding of the world.