A common tactic of the scientifically-minded “new atheists” has been to pre-emptively define faith as an irrational belief in the absence of evidence, and then to ask you how you could believe such a ridiculous thing. Professor Randall Rauser takes on this dishonest tactic here:
“While such definitions that pit faith against reason are nothing new (Mark Twain defined faith as “believing what you know ain’t true”), they have always been utterly spurious, baloney, a mere canard. A much more plausible definition of faith emerges when we consider philosopher Anthony Kenny’s definition of reason. Kenny defines reason as the mean between skepticism and credulity, that is, the optimal balance between inappropriate belief and inappropriate doubt.
But why think Kenny’s definition is true? Let’s consider a quick example. These days those who tend to reject faith typically are enamored of science. One of the cornerstones of science is observation, and the cornerstone of observation is human sense perception. This raises a crucial question all too often overlooked by the devotee of science: how do we know that sense perception is reliable?
Philosophers have long attempted a non-circular way to defend the reliability of sense perception (that is, a demonstration that does not depend already on the reliability of sense perception). But there are only two avenues that one might accomplish such a proof: either through pure rational reflection or empirically (that is, through sense perception). Sadly all attempts at the former have failed woefully: we can’t establish through reason alone that sense perception is reliable. As for the second alternative, it depends on the very thing that needs to be proved: i.e. the reliability of sense perception!”
As John Paul II illustrated, faith and reason are twin wings, both necessary for the operation of the human mind. No Catholic should accept a so-called “faith” in arbitrary ideas lacking in any reasonable evidence. Catholics do not endorse what apologist Arnold Lunn called “fif”, that is a “funny internal feeling”, as evidence of truth. What we do endorse, in addition to the truths discovered by observation and philosophical reasoning, is the historically and evidentially credible testimony of revelation, found in the one God-made-man, Jesus Christ.
(Thanks to First Thoughts)