  Category theory has foundational importance because it provides conceptual
lenses to characterize what is important and universal in mathematics---with
adjunctions being the primary lense. If adjunctions are so important in
mathematics, then perhaps they will isolate concepts of some importance in the
empirical sciences. But the applications of adjunctions have been hampered by
an overly restrictive formulation that avoids heteromorphisms or hets. By
reformulating an adjunction using hets, it is split into two parts, a left and
a right semiadjunction (or half-adjunuction). Semiadjunctions (essentially a
formulation of a universal mapping property using hets) turn out to be the
appropriate concept for applications in the life sciences. The semiadjunctions
characterize three principal schemes with applications: 1. determination
through a receiving universal (e.g., natural selection, perception, language
acquisition, recursion, and language understanding); 2. determination through a
sending universal (e.g., intentional action, DNA mechanism to build amino
acids, hierarchy of regulatory genes to build organs, stem cells, and language
production), and 3. two-way determination with one universal as both receiving
and sending (e.g., perception/action and language understanding/production).
