I recently had one of these apparent contradictions brought to me by a student. The issue is how to appropriately handle a foolish person.
Proverbs 26:4-5 NASB
Do not answer a fool according to his folly,
Or you will also be like him.
Answer a fool as his folly deserves,
That he not be wise in his own eyes.
Proverbs 26:4-5 KJV
Answer not a fool according to his folly, lest thou also be like unto him.
Answer a fool according to his folly, lest he be wise in his own conceit.
Well then.Somebody is either arguing with himself or forgot what he just said, right?
On the spot, I see two possible ways to reconcile these obvious opposites with each other. Firstly, the author could be merely stating an apparent reality. In other words, "It seems that if you answer a fool, you become foolish, but if you don't, he thinks he's wise!" Frustrating indeed. While the Proverbs often do this, it is not the only possible reconciliation.
I hoped to find some help by looking up the phrase "according to/as his ...deserves" in the original Hebrew. Maybe they are different words for the two lines.
No dice. They were identical.
So the author used the exact same phrase twice. Don't answer a fool according to his folly, just like it deserves. Better yet, do it.
I found one other instance of this phrase in the Hebrew Bible that was of some help. At the end of Job, God is correcting Job's frenemies for their foolishness and says:
"Now therefore...offer up a burnt offering for yourselves, and My servant Job will pray for you For I will accept him so that I may not do with you according to your folly, because you have not spoken of Me what is right, as My servant Job has." (Job 42:8 NASB)The phrase seems to indicate a relationship of authority giving punishment. This works, as the context of Proverbs 26:1-5 is all about putting a fool in his rightful place...downward.
Finally I found some help from early interpretive tradition: the Septuagint. This is the attempt of Jewish scholars to translate their writings from Hebrew into Greek completed in the 2nd century BC. They rendered the phrase "according to" in two different ways in the two verses. They used "pros" in verse 4 and "kata" in verse 5.
There is a slight nuance in meaning difference here. Pros seems to indicate going toward something else on the same level. I would answer pros my wife if she asked a question. Kata seems to refer to a downward approach as with one in authority. I would answer kata my son if he challenged me. The result is something like you see in the NASB translation above. Don't answer a fool toward or on the same level with his folly. Do put his foolishness in its rightful place.
Of course, the practical reality is that one is usually a poor judge of whether the other is a fool. It seems that the answer should only be given to correct a person that you are in intellectual authority over. Otherwise, it will look like the conversation of two fools.
Never argue with a fool; onlookers may not be able to tell the difference. - Mark Twain?