Being is a different kind of thing from what one encounters in the physical or mathematical sciences, even though it is given in experience (it is even the first thing in experience). The objects of other sciences have genera, species, and individuals of a species; but there are no species or individuals of a species in being. Being has no species, even while remaining fully present in any individual. This utterly unique nature of the metaphysical subject is not limited to being simply as being, it radiates outward to raise questions about goodness truth, causality, etc, and then it radiates further to raise questions about these concepts when tey are intertwined: “the cause of goodness” or “being as person” ( so far as the metaphysician studies him the person is, in his own way, being as such).
Being is more different from mathematical and physical objects than either of these objects are from each other. If we know that a complete physics will not solve all the problems of, say, algebra, a fortiori it will not solve all the problems of metaphysics- indeed, it won’t even raise them.
Notice- and this is important- metaphysics is not separate and irreducible because it deals with abstract things or general concepts. Metaphysics deals with something extremely concrete: being is just there. You can touch it, move it around, etc. It just isn’t limited to that. Again, the abstract, as such, is not found concretely except in a species or individual of a species, but being is not like this.