Luxury, or a refinement on the pleasures and conveniences of life, had long been supposed the source of every corruption in government, and the immediate cause of faction, sedition, civil wars, and the total loss of liberty. It was, therefore, universally regarded as a vice, and was an object of declamation to all satyrists, and severe moralists.
David HumeNothing is demonstrable, unless the contrary implies a contradiction. Nothing, that is distinctly conceivable, implies a contradiction. Whatever we conceive as existent, we can also conceive as non-existent. There is no being, therefore, whose non-existence implies a contradiction. Consequently there is no being, whose existence is demonstrable.
David Hume