Faith has two manifestations for the human spirit:
One is faith as mystery:
In this case, the human being witnesses a real event, a true event, one that cannot be rejected or repudiated, yet which cannot be rationally explained. Whether on is discussing the effortless flight of a bumblebee, whose anatomical construction renders it in theory aerodynamically inaccurate, or the love between two people who strike many as incompatible, these events do occur in real time. They cannot be explained, but they do occur.
The other is faith as probability.
Our minds function more along this form of faith, whether human beings concede this fact or not. That the sun will rise tomorrow, that I will be alive, that the job site where an individual works will be there, all are ultimately acted upon as a matter of fact, since there is no certainty of these events or phenomena occurring until they actually do.
Human beings operated on faith as probability all the time. Our assumptions generally work out: the sun does rise, we are still alive, our workplaces -- whether we like it or not -- are still there waiting for us.
Yet the faith as mystery requires each of us to face the ultimate questions of reality and purpose. The environment we live in, the world where we find ourselves, the intricacies of the human organism, all cry out, all witness to some intelligent design at work. Yet the source and identity of this designing force puzzles many, who or what it is, how it came -- or comes -- about, and what they whole creation was about in the first place, come to surface in the mind.
The wind, too, and other natural phenomena, exist in nature, yet defy concrete, extensive rational explanation. Though an observer does not see the wind, yet each person senses the effects of the wind, whether as gentle breeze or terrifying hurricane.
Whatever explanations one conjures up to explain these outrageous, initially inexplicable phenomena, all fall under the category of faith as mystery.