What was new in Hume's views on religion?
In his Dialogues Concerning Natural Religion (c. 1750s), Hume argued against both a priori and empirical proofs for the existence of God. This was an attack on rational grounds for religious belief. His argument against a priori arguments or the ontological argument used by René Descartes (1596-1650) was to claim that nothing that exists can exist necessarily. That is, it is not a logical contradiction to assert the non-existence of anything, including God.
His empirical arguments were mainly directed against the cosmological argument and the argument from design. Against the cosmological argument that held the world must have had a maker, Hume claimed that we do not have enough knowledge about the origins of worlds to justify a hypothesis about how this one came about. The "argument from design" held that just as things such as houses and watches must have builders, the world, insofar as it works well within itself, must have a designer. Hume's response was that we have no grounds to reason from what is true of any one thing within the world to the entire world itself. If Hume's arguments hold, then the only grounds left for religious belief are those of pure faith.
What was unusual about Hume's theory of the emotions?
Although Hume exalted reason over faith when it came to knowledge, when it came to human psychology he believed that we are primarily motivated by our emotions or "passions" and that reason is always in the service of these emotions. That is, unlike Benedict de Spinoza (1632-1677), he did not have a cognitive theory of the emotions, according to which what we feel is the result of what we believe. Hume wrote: "Reason is, and ought only to be, the slave of the passions."
Did Hume believe that we have free will?
Yes, Hume believed in free will, but in a strange way. He argued that our freedom is based on the fact that we are determined by our existing character. If there were no causal link between our motives and our actions, then there would be no moral basis for praise and blame. That is, we do not praise or blame others for what they do accidentally or as "flukes." For Hume, freedom therefore consists in the liberty to do what we want, or a lack of constraint. Our spontaneity is not the same as indifference, or the lack of a cause for doing one thing or the other. He wrote: "By liberty, then, we can mean a power of acting or not acting, according to the determinations of the will ____ Now this hypothetical
liberty is universally allowed to belong to every one who is not a prisoner and in chains."
How was Hume a man of contradictions?
Hume is famous for having written, "Be a philosopher, but amidst all your philosophy, be still a man." Hume described himself as "a man of mild dispositions, of command of temper, of an open, social, and cheerful humour, capable of attachment, but little susceptible of enmity, and of great moderation in all my passions." During his last painful illness with cancer, when his friend Adam Smith (1723-1790) visited him, he was calm and had no regrets about his atheism, nor did he desire to make a religious conversion in case there was an afterlife. He did in fact have a lifelong reputation of being pleasant and highly reasonable. He was known as the "the Good David," in England and "le bon Davide" in France.
But, concerning his moderation, Hume very much enjoyed fine food and drink and weighted over 300 pounds. And as for his mildness, his "friendship" with Jean Jacques Rousseau (1712-1778) suggests otherwise. When Rousseau was given refuge in England, partly due to Hume's efforts, in 1766, Hume soon came to regret it. Although le bon Davide had enjoyed great fame in the salons of Paris, Rousseau was a world celebrity of greater wattage. Rousseau was also financially pressed and very sensitive to public opinion. He wore exotic costumes and was made fun of in staid English society. Hume did nothing to temper this reaction. Rousseau soon became distrustful of Hume's friendship and accused him of perfidy. Instead of letting the matter rest, Hume published their correspondence, going against the advice of his close friends, who were prepared to make allowances for Rousseau, because they knew how personally troubled he was. This publication, together with Hume's denial that he had himself "leaked" the letters, destroyed his friendship with Rousseau and incurred skepticism about his own good will, good sense, and underlying motives.