Faith (saddhà) is the acceptance of the truth of an idea that cannot be known at present or that cannot be known by other means. According to most theistic religions, faith has a metaphysical effect. God requires faith and those who have it are rewarded by being saved. In Buddhism faith is understood differently. Faith is valued if it engenders a willingness, firstly, to be open to the Dhamma, next, to start practising it, and then to persist until results come. If a person did not have at least some faith he or she would never even consider the Dhamma. The Buddhist philosopher Nàgàrjuna put it well when he said: `One associates with the Dhamma out of faith but one knows out of understanding. Understanding is the chief of the two but faith comes first.' At a certain point, however, faith starts to be replaced by knowledge based on personal experience.
Buddhism distinguishes between baseless faith (amålikà saddhà) and reasoned faith (àkàravatã saddhà). Faith that is activated by a strong appeal to the emotions, by being impressed by supposed miracles or which leads one to accept the first thing one encounters, without having examined alternatives, would be examples of the former. Reasoned faith grows out of a careful assessment of probabilities, inferences and facts.
This attitude is well illustrated by an encounter between the Buddha and a man named Upàli who was a respected community leader and a follower of Jainism. After a long discussion with the Buddha, Upàli decided to become his disciple `from this day onward for as long as life lasts'. But rather than accept Upàli's avowal of faith the Buddha urged him to take time to consider carefully before making such an important decision: `Make a careful investigation, Upàli. It is appropriate for well-known people like yourself to make a careful investigation first.'
At this time in India there was considerable competition between the various sects to get disciples and Upàli was surprised by this unexpected advice: `I am even more pleased by what you say. If another sect had secured me as a disciple they would have paraded a banner through the town to let everyone know. But you ask me to make a proper investigation first.' Knowing that Upàli had been a Jain the Buddha then asked him to continue supporting his former religion: `For a long time your family has given alms to the Jains. Continue giving them alms when they come.' (M.I,379).
According to the Buddha, rational faith is `rooted in understanding, strong, not to be shaken by any teachers or preachers, devils, gods, God, or by anyone in the world' (M.I,320) and thus does not need to be buttressed by close-mindedness or a partisan attitude to other religions. See Trust.