The doctrine of the Trinity is the Christian answer to the old problem in philosophy of “the one and the many.” Think of your own family. How does your family structure reflect and even answer “the one and the many”? Think of other parts of your life where this dynamic of “the one and the many” is evident.

I think for me this argument reveals itself in self versus group. As a member of the family, I have a role as an individual; my role is different from that of my wife or my children. In my extended family, my role changes as my relationships grow and develop, or wither and die. Without me, the family is incomplete in some ways. This dynamic is none to often revealed when a family member reflects on a lost one: " he / she always used to do that". 

We can see the one and the many in a lot of areas. In a car, you have a variety of parts, each with their own role, yet each one is essential for the car to run at peak performance. If one part is lacking, it can cause undue wear on other parts. It won't be long before a car breaks down if a part is not functioning properly.