Francis Bacon’s most important book, The Advancement of Learning, is remarkably modern. He is commonly regarded as the originator of the saying ‘Knowledge is power’.
The basis of his philosophy was practical: to give mankind mastery over the forces of nature by means of scientific discoveries and inventions. He held that philosophy should be separate from theology, not intimately blended with it as in scholasticism. He accepted orthodox religion; he did not quarrel with the government on such a matter. But
while he thought that reason could show the existence of God, he regarded everything else in theology as known only by revelation. He held that the triumph of faith is greatest when to the unaided reason a dogma appears most absurd.
But philosophy should depend only on reason. He was an advocate of the doctrine of ‘double truth’, that of reason and that of revelation. This doctrine had been preached before but had been condemned by the Church. The ‘triumph of faith’ was, for the orthodox, a dangerous device. Bayle made ironical use of it, presenting at great length what reason could say against some orthodox belief, and then concluding ‘so much the greater is the triumph of faith in nevertheless believing’.
It is impossible to know how sincere Bacon’s orthodoxy was.
Bacon was the first of the group of scientifically minded philosophers who have have emphasized
the importance of induction as opposed to deduction. He tried to find some better kind of induction than what is called, ‘induction by simple enumeration’.
Induction by simple enumeration can be illustrated by a parable.
There was once upon a time a census officer who had to record the names of all householders in a certain Welsh village. The first that he questioned was called William Williams; so were the second, third, fourth…. At last he said to himself: ‘This is tedious; evidently they are all called William Williams. I shall put them down so and take a holiday.’ But he was wrong; there was just one whose name was John Jones. This shows that we may go astray if we trust too implicitly to induction by simple enumeration.
Bertrand Russell, A History of Western Philosophy
Bacon believed induction could be better than this. He wanted to discover the nature of heat, which he rightly thought consisted of rapid irregular motions of the small parts of bodies. His idea was to make lists of hot bodies, cold bodies, and bodies of varying degrees of heat. He hoped to find a characteristic present in hot bodies but nonexistent in cold bodies, and present in varying degrees in bodies of different degrees of heat. Through this method, he expected to arrive at general laws.
Bacon the syllogism, and undervalued mathematics, presumably as insufficiently experimental. He was hostile to Aristotle but thought highly of Democritus. Although he did not deny that the course of nature exemplifies a divine purpose, he refused teleological explanations in the actual investigation of phenomena.
He valued his method as showing how to arrange the observational data upon which science must be based. We ought, he says, to be neither like spiders, which spin things out of their own insides, nor like ants, which merely collect, but like bees, which both collect and arrange. This is somewhat unfair to the ants, but it illustrates Bacon’s meaning.
Bertrand Russell, A History of Western Philosophy
Bacon’s philosophy is famous for his list of ‘idols’, by which he means bad habits of mind that cause people to fall into error. Of these, there are four kinds.
‘Idols of the tribe’ are those that are inherent in human nature; especially the habit of expecting more order in natural phenomena than is actually to be found. ‘Idols of the cave’ are personal prejudices, characteristic of the particular investigator. ‘Idols of the market-place’ are those that have to do with the tyranny of words. ‘Idols of the theatre’ are those that have to do with received systems of thought.
Bertrand Russell, A History of Western Philosophy