There should be no doubt in the believer's mind that evangelism is a critical aspect of the faith. Unfortunately the reality can be that whether or not we do oft times depends upon the person we are speaking with. Responses we get can be very frustrating and sometimes even stump us. People we share the gospel can be very unreasonable, especially in their attempts to use reason to refute what we are saying.
There are three basic areas, root assumptions, if you will, that should not be yielded in our conversations. Not yielding in these will ensure that we not be forced to engage in pointless unreasonable debates. These assumptions are the core to any reasonable conversation.
First, is that we do not deny the Law of Contradiction. Simply stated it says "A cannot be non-A and A at the same time and in the same relationship". This law is a universal guide for coherency and a formal test of logic.
Philosopher Renee Descarte asked if something could be both formally true and materially false. That is, could something that we think to be real be not real. A unicorn is an example proving so. We can imagine, or create one, in our mind yet that does not mean it is so. John Locke asked the opposite; Can something be materially true and formally false. Can there be something that we can not have an idea about? That would be non-reality. Kant said that if this was true then we could know nothing, and all knowledge would cease. (BTW this is the root of postmodern existentialism but we'll discuss this another time).The Enlightenment thinkers validated the Law.
Christians are accused of breaking this law frequently, however untrue it is. For instance, we say God is three and one. Seemingly this is a contradiction, yet it is not, philosophers call this a paradox, that which appears to be a contradiction. When we say this we are not saying He is one God and three Gods, we are saying He is One in essence and Three in persons. One A and three B's. Not a contradiction but a paradox. How can this be, we do not know, it is but a mystery for a mystery is something we can not comprehend, yet does not break the law of contradiction.
We encounter much lack of knowledge of these significant differences leading to untrue statements from those we chat with that we might shun away from them. Our own knowledge of the difference is imperative to our discussion.
To have any reasonable conversation the Law of Contradiction must be maintained. We must be able to defend it, and we must recognize when it is being broken by others. For instance, to say the universe existed and did not exist at the same time breaks this law, and is deemed incoherent and unreasonable. But to support the "Big Bang" one must state exactly that.
In our next chat we will look at the Law of Causality, the second law we must maintain to engage in an unreasonable discussion.