Nor are the earth, water, and other elements, examined by ARISTOTLE, and HIPPOCRATES, more like to those, which at present lie under our observation,… - David Hume

But where the ideas of morality and decency alter from one age to another, and where vicious manners are described, without being marked with the proper character of blame and disapprobation, this must be allowed to disfigure the poem, and to be a real deformity. I cannot, nor is it proper I should, enter into such sentiments; and however I may excuse the poet, on account of the manners of age, I can never relish the composition.

When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume of divinity or school metaphysics, for instance, let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames, for it can contain nothing but sophistry and illusion.

starting with Martin Luther’s rebellion against the Church of Rome in 1517, led to widespread religious wars founded on philosophical differences: one side took Church authority and tradition as the criterion of truth, the other appealed instead to the Spirit of God acting within the individual believer.