What is faith? For this question you should consider and evaluate more than one interpretation of the concept of faith.

The empirical world cannot give proof for the existence of God and therefore cannot form a basis for religious knowledge. What is largely left of religious beliefs is faith. There are a number of interpretations of what faith in any religious sense is. They range from the purely logical argument to the fully passional. Faith need not be grounded in religious belief at all. Belief in the scientific method may well be described as an act of faith as it can lay the foundation for knowledge of nature.

Aquinas believed that faith is a form of belief, between knowledge and probable opinion. Our will enters into what we claim to know. We make a choice, an inner assent, between beliefs. According to Aquinas faith is needed by the many as only a few receive religious knowledge by revelation.   The many hold propositions to be true, such as the existence of God, as an act of faith.   Aquinas’ faith is a belief-that. It emphasises propositional belief to the detriment of experiential belief.

So the prepositional beliefs held by Aquinas can have insufficient evidence to fully justify the beliefs. Without the evidence the beliefs can be irrational.

Pascal’s account of faith is known as Pascal’s Wager.   It is a choice given probabilistic outcomes of an individual’s choice. Faith for Pascal derives from an examination of four possible ways to lead your life. There is a personal decision to believe in God, or not. If there is a God then it is prudent to believe in Him, in order to derive the greatest happiness in this life or the next. If there were no God then it is still prudent to believe that there were and act accordingly, just in case there is a God! If there is no God, and no belief in God then a person loses nothing, but also gains little. According to Pascal a person has to choose, as it is their life they are wagering.

For one of the greatest mathematicians of his time this was a crafted choice of probabilities that somehow seems to be almost cynical.

If one type of God exists then why not another? The nature of a God could be such that there are no rewards.

Pascal’s wager misses the point of commitment in one’s beliefs and the leading of one’s life. That the wager must be made also presumes a belief in the fear of damnation (loss of eternal happiness) if the choice is against a God that turns out to exist. The no loss argument for leading one’s life as if there was a God misses the power of faith in one’s own beliefs, and the doubts. To act without faith in God’s existence, but live a life as if God exists is to live in bad faith. For Christian beliefs this would still lead to damnation because there is no repentance.

William James’ ideas on faith are described in terms of hypotheses, or beliefs. For an individual there are live and dead hypotheses according to the individuals interests and needs. Each live hypothesis of how to lead their life is further categorised as forced or avoidable. What James went on to describe was forced hypotheses, ones that an individual could not avoid, such as how to live one’s life. A momentous hypothesis such a belief in the existence of God could not be avoided, as a choice has to be made in one’s life that can only be based on faith. The option is genuine when it is living, forced and momentous.

James not only criticised any act of faith based only upon probable outcomes such as Pascal’s but also faith only being based on beliefs based entirely on rational grounds such as evidence. Both views he saw as an unrealistic view of what faith is.

Nearly all our beliefs are based upon assumptions that are taken on trust. The beliefs and faith in them come before rational argument or empirical findings. James argued that making hypotheses is part of our nature.

According to James there are two principal ‘passional’ urges in an individual’s life. They must strive to know the truth and must avoid error. In order to achieve these goals an individual is faced with non-trivial, ‘live’ hypotheses of life and how to lead it that cannot be avoided. For trivial options there is no need to accept as a matter of faith an hypothesis, there can be scepticism. It is for the momentous options that an individual cannot wait for empirical evidence or logical argument to settle the matter. An individual has to choose a way of life and a set of moral beliefs.

James does capture more of the passionate commitment needed to lead one’s life, than does Pascal. It is not as arid an argument for faith as is Aquinas’. The choice is still blind, as in Pascal’s wager, but more to do with involvement of an individual in leading their life.

The religious hypothesis could be a delusion. James does not offer any way of confirming or rejecting the live, forced, momentous option. The hypothesis cannot be verified. Whether an hypothesis is live or dead is a purely subjective, emotional response by the individual. That may mean losing any objective reasoning about our beliefs.  James’s hypothesis and the options of live, forced and momentous lead to a ‘weighting’ of values towards the religious experience. However a live and forced choice to believe in God still does not make it momentous, ‘non-trivial’. An individual can believe in God, can be forced by argument, inner assertion and experience to believe in the existence of a God. This may not mean a momentous decision though, for that individual may not classify that belief as engendering more meaning to their life than there is no Santa Claus, whatever weight James may have put on his classification.

According to Kierkegaard faith is the experience of belief. It involves total commitment to one’s belief without reliance of proof. Faith is a total belief-in or state-of-mind, not a belief-that. Kierkegard’s faith is at the other extreme to that of Aquinas. It is purely subjective and not based upon reason at all.   That knowledge is possibly unattainable is irrelevant to his concept of faith. The individual has to choose a life and suffers dread and despair in making choices for a life. That there are infinite choices and that there may be no ‘right’ choice is central to Kierkegard’s, and future existentialist thinkers view of faith. A ‘leap of faith’ is needed to overcome indecision and dread.

The individual’s will seems to play a larger part in a concept faith from Aquinas to Kierkegard. Faith is a personal thing that may not really be described in an objective way at all. When all debate is done the one thing left of an individual’s belief is faith. It may be described as one aspect of a person’s individuality that may not be rationalised, without fear of undermining any real sense of purpose in life.