Faith, says STA, is like opinion so far as both are the assent to a proposition that is less than evident, but faith differs from opinion by being unwavering and completely certain. But this seems like satire – isn’t this exactly the sort of New Atheist account of faith that an apologist is supposed to dismiss as silly and uninformed? STA is literally defining faith as absolute certitude in the absence of evidence! Who wrote this part of the Summa? Richard Dawkins?
That said, faith is an inescapable part of human life. Every sports fan has faith in his team, not in the sense that he always thinks they will win or that everything they do is good, but because his commitment to them is unwavering. That your team is to be praised or loved is not a belief formed from a cool-headed evaluation of its merits, and it is not to be thrown out by a careful evaluation of a team that might be more worthy of your devotion. Students develop the same sort of faith in schools, along with a corresponding hatred for the school’s rivals. Faith can have reasons, but never ones that could justify the sort of devotion we give to the team or institution.
Faith is responsible for the better and more personal parts of life, since every vow and every pledging of one’s life is an act of faith. A cool-headed evaluation of reasons could not justify the unwavering and absolute commitment that spouses make to each other, citizens make to their regime, or soldiers make to their country. As Chesterton put it, no soldier will die for pay. This degree of fixity, commitment, and certitude does not arise from seeing that the object of the vow in merits the degree of assent but because, as John Paul II said somewhere, love can’t be entered into on a trial basis. You either commit to the whole thing before you know the whole thing, or you’ll neither know it nor love it.
So faith turns out to be the fullest flower of the teaching that Plato gives in Phaedrus: The highest gifts are the convictions that come to us from the gods as mania, beyond the reach of reason or evidence.
There’s a large scholarly consensus that one lasting legacy of WWI was the destruction of faith. Love of country, honor, and patriotism all became conditional commitments tinged with irony. Faith was for rubes and suckers – nothing more than buying into to a self-interested propaganda campaign of the rich and powerful. My own generation (I’m as Gen-X as they come) prides itself on “knowing” this too, but this is probably related to living through the highest divorce rate ever (and a corresponding dip in the marriage rate). Both of these generational facts have a dynamic relationship with the losing of religious faith. The Nietzschean death of God is both cause and effect of a corresponding death of God and family, i.e. the belief that faith in the fatherland or in fathers is no longer believable.