"differentiation"

... No, I'm NOT using the subject-term in a mathematical sense (Although, I COULD.).   When I brush my teeth, I've noticed that I'm able to--SUBCONSCIOUSLY--separate my EXCESS saliva from my toothpaste.  THANKFULLY!  The fact that I don't even have to "THINK ABOUT"/"CONCENTRATE ON" this process is quite the relief!  I have ENOUGH "ISSUES" about which to worry!   Plus, I HAVE A BRAIN-INJURY!    ((NOW, I have to get back to "deriving some Calculus problems" ("differentiation").))