Our understanding of our real problem as human beings will determine the solution we think we really need. If the problem is economic, we may propose economic solutions like having equal opportunities for all or lowering the inflation rate or interest rate, etc. If the problem is ignorance, we would assume knowledge is the key. Let's put up more schools, etc. If we think the problem is criminality, let's put more people in jails or let's come up with more laws, etc. In other words, if we don't understand the real problem, we will always come up with the wrong solutions. For Paul, our universal problem is sin, and the only real solution is the Gospel.