Faith is trust, hope and belief in the goodness, trustworthiness or reliability of a person, concept or entity. It can also refer to beliefs that are not based on proof (e.g. faith that a child will grow up to be a good person). Religious faith is a belief in a transcendent reality, a religious teacher, a set of teachings or a Supreme Being. Generally speaking, it is offered as a means by which the truth of the proposition, "things will turn out well in the end," can be enjoyed in the present and secured in the future. Religious faith appeals to transcendent reality, or that reality which is beyond the range of normal physical experience (e.g. the future).
Transcendent reality, therefore, constitutes a reality which is off limits to material measurement and other rigors of scientific inquiry such as falsifiability and reproducibility. Most atheists and some agnostics criticize religious faith as superstition, categorizing it with other forms of belief that are not based on observable material things.
Informal usage of the word faith can be quite broad, and the word is often used as a mere substitute for trust or belief. The English word is thought to date from 1200–50, from the Latin fidem or fidēs, meaning trust, derived from the verb fīdere, to trust.
Some critics of faith have argued that faith is opposed to reason. In contrast, advocates of faith argue that the proper domain of faith concerns questions which cannot be settled by evidence. This is exemplified by attitudes about the future, which (by definition) has not yet occurred. Logical reasoning may proceed from any set of assumptions, positive or negative. In this view, faith is simply a positive assumption.