In its strong form, the thesis that there is no reality behind appearances. Thus, it is the job of science to catalog the formal relations which hold between appearances without claims of describing reality. See phenomenalism A weaker form of empiricism admits of the existence of a reality which is, however, trans-empirical. The transcendent nature of reality determines that we can have no knowledge of it and thus must simply catalog the formal relations between appearances.
Empiricism is very much like phenomenalism .
However, empiricism is a term more commonly used in philosophy of science than philosophy of mind . In either case, these positions are most commonly contrasted with realism .