Faith is the process that creates, fleshes out, and revises ideas in yourself and others sufficiently to generate actions that would not otherwise occur, yielding physical outcomes that would not otherwise be.
A person’s faith can therefore be measured in terms of the frequency and degree of outcomes that have occurred that would never have otherwise come to pass.
Detractors claim that “ye cannot know of things which ye do not see.” (Alma 30:15) However, things which we don’t yet see are an integral part of all progress in life.
It is essential to understand that the outcome of faith will always include actions, thoughts, and feelings that are different than what you had before you exercised faith. If they did not change, it would be impossible for you to bring to pass anything different than what you were capable of before exercising faith.
Faith creates reality independent of what already exists:
Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear. (Hebrews 11:3)
We receive no evidence of a belief until after we test it by first living it. Even adopting something we have observed to work for another has no guarantee of reproducibility until after it is tried. We live according to the belief that you can know of things which you don’t see every single day. To claim that this principle somehow doesn’t apply to spiritual things in the same way it does to everything else in our lives is simply absurd.