Faith is to believe what you do not see; the reward of this faith is to see what you believe.Saint Augustine — as attributed
Applied faith is Napoleon Hill's term for the active, directed form of belief — not passive trust in an external power, but the sustained conviction that a specific goal is both worthy and achievable, combined with the consistent action that that conviction requires. It is faith put to work, not as a substitute for effort but as its generator.
Hill distinguished applied faith from hope, which he regarded as a wish without a plan, and from blind faith, which ignores evidence. Applied faith begins with a clear Definite Chief Aim — a specific, written statement of what is to be achieved — and maintains confidence in that aim not because success is guaranteed but because the conviction itself is necessary for the quality of effort that makes success possible. The person who half-believes in what they are doing brings half their capacity to it. The person who believes completely brings everything.
The psychological mechanism behind this is not mystical. William James observed that the belief in a fact can help create that fact — not in the sense that belief produces miracles, but in the sense that the person who believes they can accomplish something approaches the attempt with a quality of attention, persistence, and creativity that the person who doubts they can accomplish it simply does not bring. The outcomes differ not because of metaphysics but because of the difference in effort, creativity, and resilience between the two approaches.
James Allen, writing in 1903, made the same point without Hill's framework: a person is literally what they think. The character that thought produces shapes the habits of action that produce external results. Applied faith is, in this account, the deliberate cultivation of the thought pattern — the consistent orientation of attention toward what is to be achieved rather than toward what might prevent it — that generates the character which generates the results.