[StJacques]

"By means of metaphysics we may know all of science."

Only if you postulate or assume a priori that it is possible to know all of science through metaphysics. A priori reasoning is deductive in nature, and relies upon logical system building, while science is inductive in nature, and relies upon empirical validation, or a posteriori reasoning. In other words, your statement is only true if you assume that it is true.

"By means of science we may not know all of metaphysics."

Actually, by means of science you may know almost nothing of metaphysics.

"What does that say to you?"

It says that you cannot separate a priori from a posteriori reasoning and that you misapply deductive logic when empirical validation is required.

"See 'subsume.'"

[unspun]

In other words, your statement is only true if you assume that it is true.

St.J, "metaphysics" (or use another word, if you prefer... epistemology) is the study of all ways we may know or understand. Therefore all of science is subsumed by metaphysics.

[unspun]

In other words, your statement is only true if you assume that it is true.

(I realize that materialists choose to marginalize the concept of "metaphysics" as etherial pie in the sky bye and bye, but I'm talking about the disciplines involved in what has consistently been called by that term, in Western Civilization. So, go ahead and substitute "epistemology" in that post, yesterday. And when I refer to science there, I am referring to how we may understand via the scientific method.)