Methodical and non-circular Catholicism

Having seen another good theological debate destroyed by ad hominem attacks, I do muse on the method that people use to settle questions of Moral Theology in this day and age. Scientific method has been, in some sense, born out of the traditional Church's method of enquiry.

As I see it the method goes as follows:

1) Form the Question.
2) Perform experiment.
3) Make Observations
4) Interpret Observations.
5) Form Conclusion.

So for example:

1) Does this stone float?
2) Drop it in water tank.
3) The stone is now at the bottom of the water tank.
4) The stone has sunk.
5) The stone doesn't float.

In Moral Theology, the question is usually "Is it right to X?" The same method gives us:

1) Is it right to X?
2) Read the Holy Scriptures for information about X.
3) Collate texts about X from Holy Scriptures.
4) Check interpretation of those texts in Church Tradition.
5) Form a conclusion.

E.g.

1) Should I sleep with that man's wife?
2) Read Exodus
3) Exodus xx.14: "Thou shalt not commit adultery"
4) "There is this further, that in that very debt which married persons pay one to another, even if they demand it with somewhat too great intemperance and incontinence, yet they owe faith alike one to another. Unto which faith the Apostle allows so great right, as to call it ‘power,’ saying, ‘The woman has not power of her own body, but the man; again in like manner also the man has not power of his own body, but the woman.’  But the violation of this faith is called adultery, when either by instigation of one's own lust, or by consent of lust of another, there is sexual intercourse on either side with another against the marriage compact: and thus faith is broken, which, even in things that are of the body, and mean, is a great good of the soul: and therefore it is certain that it ought to be preferred even to the health of the body, wherein even this life of ours is contained." (St Augustine, De Bono Coniugali iv)
 5) I shouldn't sleep with that man's wife.

Of course, that's a very simplistic answer to a well-established question and there are bits we need to consider such as circumstance, intention, or even whether the husband is actually still alive.

However, there is another method being used in the current clime:

1) Should I sleep with that man's wife?
2) I have the gut feeling that it's right to sleep with that man's wife and lots of people seem to be doing it.
3) I John iv.7 "Beloved, let us love one another: for love is of God; and every one that loveth is born of God, and knoweth God."
4) In Exodus xx.14, recent scholarship shows that adultery doesn't mean what we now think it means.
5) I should sleep with that man's wife.

Yes, I know that is a bit of a straw man argument. To be honest, I can't think of an argument that supports adultery - perhaps I'm just not that imaginative - but this is the shape that arguments for recent decisions in Moral Theology seem to be following. Perhaps wiser people would put me right.

This new method seems to be.

1) Form the question.
2) Answer the question based on subjective observations and social conventions.
3) Read Holy Scripture/Tradition to find the bits that fit.
4) Discredit the bits of Holy Scripture/Tradition that don't fit using "modern scholarship".
5) Justify the Conclusion formed in (2).

A rational human being would discredit the New Method on the grounds that it assumes the thing it's trying to prove. It is a circular argument problem, just like

A) God exists.
B) God caused the Bible to be written.
C) Therefore the Bible is infallible.
D) The Bible says God exists.
E) Therefore, God exists.

I still see arguments like that from supposedly learned scholars trying to prove the infallibility of the Bible. It doesn't work and doesn't convince anyone.

If we have a moral question, then we usually have a vested interest in the conclusion - we'd like X to be morally right because we enjoy it. However, as Christians we must concern ourselves with the Truth. Christians have to believe in an objective Truth simply because Our Lord specifically says, "I am the Way, the Truth and the Life". If there is an objective Truth, then we have to suspend our desire for X to be morally right in order to put it through objective tests to discern whether it is. The Old Method is objective and there is no room for subjectivity. We can then rule our bodies by making them conform to the objective moral truth that Christianity provides.

If we're really set upon discovering moral truth in this day and age, then we need to take the circles out of our arguments.