Apologetics 101: First Principles
After taking last week off, I thought I would surely get back on my regular posting schedule this week. However, I have managed to find a way to be a day late, yet again. Regardless, now that we have examined the definition of apologetics, the biblical warrant, and the biblical approach to apologetics, we will move on to the various methodologies of apologetics. To begin, we must first take a look at some basic principles of logic. While, there are some Christians who would automatically dismiss the use of logic, understanding the basic principles of logic is necessary when engaging others of differing philosophical world views (how one interprets reality).
Douglas Groothuis writes
Some Christians have disparaged the use of logic in either defining or defending Christian faith on the basis that logic is ‘merely human’ and that we cannot limit God in this way. Worse yet, they have claimed that whatever benefit there may be in logic, it has been defaced by the Fall such that the human mind cannot grasp God through reasoning. On this understanding, faith means believing something without or against evidence and logic.
However, as Groothuis would go on to assert, and as we saw in an earlier post in this series, God never intended for us to have a blind faith. The Bible is full of examples of the use of evidence and logic to establish the validity of Christianity. While we, as Christians, already accept God’s Word as truth, those we are engaging in apologetics typically do not. For this reason, we utilize the basic principles of logic to evaluate the validity of their worldview and the truths they assert. Having said that, we will briefly examine four laws of logic that are used to test the validity of such claims. (As I mentioned at the beginning of this series, these posts are not intended to be comprehensive, but introductory. For a more extensive, yet easily attainable explanation of these principles, I recommend Douglas Groothuis’ Christian Apologetics: A Comprehensive Case for Biblical Faith.)
The Law of Noncontradiction
As Aristotle penned, “Nothing can both be and not be at both the same time in the same respect.” Groothuis explains, “Nothing can possess incompatible properties; that is, nothing can be what it is not. For example, Jesus cannot be both sinless and sinful.”
The Law of Excluded Middle
The law of excluded middle states that a statement of fact and the denial of that fact cannot both be true. For example, the two statements, “Jesus was sinless” and “Jesus was not sinless” cannot both be true at the same time.
The Law of Bivalence
This principle states that a declarative statement of fixed meaning (this excludes questions of interpretation since the meaning of the statement is fixed, or determined) is either true or false; it cannot be both true and false, and it cannot be neither true nor false. Take, again, the statement, “Jesus is sinless.” The law of bivalency says that this statement cannot be both true and false. It also says that the statement cannot be neither true nor false.
The Law of Identity
Ever wonder where the statement “It is what it is” originated? I’m not sure where, exactly, it came from, but it definitely applies here. The principle or law of identity simply states that a thing is what it is, or A = A. To put it another way, a thing cannot be what it is not. This does not fail to recognize the ability of something to change over time, but that it cannot be what it is and what it is not at a given time.
To one who is new to apologetics or the principles of logic, this may seem a bit overwhelming. I would encourage you, however, to dig a little deeper (see Groothuis link above) in order to gain a better understanding of these laws of logic, which are imperative to being able to not only evaluate, but to demonstrate the inconsistencies of other worldviews. Hopefully, the need for the first principles of logic will become more clear as we move into specific apologetic arguments. As always, my prayers are with you and your studies.
 Douglas Groothuis, Christian Apologetics: A Comprehensive Case for Biblical Faith (Downers Grove, Illinois: IVP Academic, 2011), p. 45.
 Aristotle, Metaphysics 1005 b19-20.
 Groothuis, 46.