Faith is about the balance between evidence and confidence.
At one end of the spectrum it's hardly appropriate to use the word at all.
Do you have "faith" that the sun will rise tomorrow? Technically I suppose we do but there is so many reasons to have confidence that it will rise it debases the word to call it faith.
At the other end of the spectrum some people have confidence in the existence of a spirit world ruled by a deity who knows our every thought. This is so out of proportion with the available evidence that it relies on the religious meme that makes a virtue out of disproportionate confidence.
The word "rational" may preserve the idea of ratio or proportion, I'm not sure.
We are only a partly rational species.