I refute that A is B.
If this structure is ok, which of the following does it mean:
- I argue that A is not B.
- I argue against some other position (such as X is Y), by arguing that A is B.
The first step in refuting something is to have an object of the refutation—George Berkeley, for example, or a specific proposition of Berkeley's, or some statement that someone else asserts is factual. In the example given in the original post, the object of the refutation is unspoken but implicit: "I refute [the proposition] that A is B." The assertion in this case amounts to saying "I prove that A is not B." To claim to refute some proposition is not merely to announce an intention to argue against that proposition, however; it is to demonstrate that the proposition is false. Whether refuting the proposition that A is B has some bearing on the validity of the further proposition that X is Y is not essential to the original refutation, though it may flow as a logical consequence from the original refutation.