"A wise man proportions his belief to the evidence."
Hume was born and educated in Edinburgh. He wrote his first significant work, A Treatise of Human Nature, whilst living in France. Although it was not well received initially on his return to Britain, it later became recognized as one of the most important philosophy books ever written.
Hume was an empiricist in the tradition of Locke and Voltaire. He was very sceptical about what he, or indeed anybody, can know. His other major works, which were also of great significance, were An Enquiry Concerning Human Understanding, An Enquiry Concerning the Principles of Morals and Dialogues Concerning Natural Religion.
"Beauty is no quality in things themselves: it exists merely in the mind which contemplates them."1
As a sceptic he believed that almost nothing about existence was demonstrable. Just because the sun always rose in the morning didn’t mean that it would rise tomorrow morning, or just because we observe a number of swans and they are all white, we conclude that all swans are white. This is 'inductive reasoning', or making generalizations from observing a number of similar cases. He claimed that inductive reasoning could not be relied upon to lead us to the truth, and as all scientific laws are, in fact, generalizations from inductive reasoning, his logical reasoning posed significant problems for those who followed him.
Hume published a number of Essays in which he addressed human happiness.
Firstly he expressed the Epicurean view that human happiness is found in pleasure (Essay 6), then the Stoic view of natural order and finding happiness through honest and hard work (Essay 7), and then the Platonist view that happiness is found in the contemplation of the most perfect object (Essay 8).
Furthermore, he argued that the best position in life is a middle rank, since the rich are too immersed in pleasure and the poor struggle for necessities. The middle position provides the best opportunity to acquire virtue, wisdom, and happiness. And he also notes that when people are lazy and indifferent to other people, then luxury is harmful to political society.
Regarding the existence of God, Hume’s position can be described as agnostic; he was sceptical, believing that it is impossible to know whether there is a God. He said, "The Christian religion not only was at first attended with miracles, but even at this day cannot be believed by any reasonable person without one."
Hume appeared to display a good understanding of those who adopted a haughty or egotistical position, much like narcissists in contemporary society, when he said, "Where men are the most sure and arrogant, they are commonly the most mistaken."
For more information about the great philosophers and their views on narcissism and happiness, read Finding Happiness.
1 David Hume, 'Of the Standard of Taste'