18) Since each Protestant must admit that his or her interpretation is fallible, how can any Protestant in good conscience call anything heresy or bind another Christian to a particular belief?

1 Corinthians 6:3 Know ye not that we shall judge angels? how much more things that pertain to this life?

Evidently Paul didn't buy in to such a self defeating paradox. If our fallibility means we cannot judge what is true, then neither can we judge the truthfulness of that statement and so the proposition defeats itself.

Agnosticism, regardless who spouts it, is like a dog chasing its tail, you don't get anywhere, and it is tiring after a while.

If Catholics went through life making no judgments at all except those infallibly decreed by their Teaching Authority, then perhaps they could make this argument. But as their teaching authority has completely failed to judge every aspect of Catholic life, and yet Catholics can be found pontificating on all sorts of topics, both religious and secular, it is clear the Question is inconsistent with objective fact.

We don't need the attribute of infallibility to render judgment on what is right or wrong according to what we know to be true.

As long as we follow our conscience honestly, we are convinced God will be merciful if we make a mistake:

Romans 2:15 Which shew the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another;) 16 In the day when God shall judge the secrets of men by Jesus Christ according to my gospel.

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The times of this ignorance God winked at; but now commandeth all men every where to repent:

Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me.-kjv