that's not faith,
1 you HAVE to breath.....even if you hold your breath, you have to breath at some point, so it don't matter if you think there's air there or not, your body still gonna try to breath it.....
also.......considering that since birth, just about every breath you took had air in it, you're not expecting air on faith, it's a certainty that there is air present, and it can be proven that air is there and it is breathable....
you can 100% prove that there is air to breath by the defining fact that everyone is breathing it....
faith can not be proven