Persuasion / Tu Quoque Fallacies Persuasion.

I remember an occasion when I went on a canoeing trip with my friend David from high school. David is the sort of person who always totally speaks his mind about anything -- he is not shy about commenting (often in an almost abrasive manner) on the person you are dating, or the clothes you are wearing, or anything else that happens to pop into his mind. He organized several people from our high school to go on a river canoeing trip, mostly because it would be a good way to spend time together, and get some exercise which would not be too taxing. We went to a canoe rental place, and paid to do a 4-hour trip along an easily navigable creek: there was nothing dangerous about the canoeing part of it, the water would rarely be deeper than four feet, and there would be no chance of drowning and no rapids or anything (although we were given life-jackets). So about six of us who had been in high school together packed a picnic lunch and decided to do this as a fun activity.

The trip was fun, and relatively uneventful. We did capsize once or twice, but we had packed our lunches in plastic bags, so we were able to find a grassy area on the bank and have a picnic without having to eat wet sandwiches. The point of the story came a day or two after the trip. I met up with David again, and he pointed to my leg. "Did you get hurt when the canoe capsized?" he asked. I looked down and there was a smallish round welt or rash just above my shin, which I had not actually noticed. I told David that I didn't think I had, and I started examining the red circle on my calf -- it did not hurt, so it could not have been a bruise or a scrape. David, who is a fairly brash person, said "That's a circular rash, it's probably Lyme Disease." I was skeptical and he said, "Look, why would I make this up? We just went on a canoeing trip through the woods. That's the kind of place where people get bitten by ticks and get Lyme Disease. Get it checked out."

The truth is that I thought David -- who likes saying brash things to get a reaction from people -- was probably deliberately winding me up. The evidence of a red mark on my leg didn't seem like it could be a serious illness. Despite the fact that he was being serious, and he had nothing invested in whether or not I went to a doctor to have my leg looked at, I assumed it was probably a mosquito bite and my outspoken friend was just joking. In fact, I forgot about it until sometime a few weeks later, I started feeling agonizing pain in my joints. At this point I went on Google -- despite the fact that the pain was sudden and extreme, and it was very difficult to move or type -- and looked up Lyme Disease. I immediately made a doctor's appointment and when I went in, a blood test confirmed that David was, in fact, right -- I did have Lyme Disease, and was promptly put on antibiotics. After several weeks the infection went away, and the doctor declared I was clear.

The fact is that the evidence presented to me seemed relatively insignificant. And the person giving me the advice had nothing invested in the situation, but was also someone with a history of saying blunt and provocative things. Then again, it was David who had organized the outdoor canoe trip, and it might have been in his mind -- or he might have been warned by his parents or someone else -- that outdoors activities in the woods carry a risk of being exposed to the ticks that carry the Lyme Disease. But in retrospect, I wish...

The evidence of my own eyes was insufficient because I was insufficiently knowledgeable about what might constitute the "bullseye" rash of an initial Lyme Disease infection -- but considering that it is much easier and simpler to be treated when you get the first insect bite, rather than by the time that it moves to your body and starts causing real pain
2. Tu Quoque Fallacy

I remember when I was in high school, a number of people decided to draw sexually-themed pictures on the whiteboard before a health class dealing with sexuality. The teacher for the health class was late, and besides we were just illustrating the sorts of things that got discussed in the class. We were basically daring each other to draw these things -- and I was the fifth or sixth person to run up and draw something on the board. But as I was drawing a very large penis with a dotted line emanating from the tip, the teacher walked in.

The teacher immediately told me that I would be given a detention but I responded by saying "Uh, you realize that I didn't draw all of these." The teacher actually stepped back and looked at the various obscene drawings on the whiteboard and commented that it was obvious from the artistic style -- my drawing was not nearly as good as some of the others, and was more skillful than one or two. I tried to complain that I was only being punished for getting caught, but at the same time I had no wish to name names as to the other people who had drawn the various vulvas and whatnot which decorated the whiteboard.

My protest that I was not the first or only person to have done a drawing on the whiteboard -- despite the fact that I was the only person to be punished for it (because I had been caught in flagrante delicto) -- could be viewed as an example of the tu quoque fallacy. Yet at the same time, there must be reference in some way to prevailing standards of behavior, and the imposition of a uniform mode of justice. If the fact that five other people had done obscene drawings before I got caught drawing a sixth does not make my act any less wrong, then it is worth mentioning that punishing one person for an act to set an example for the five who have managed to get away with the same act without punishment is hardly a good example to set for those imposing justice. I suppose if I had been in a position to argue more with the teacher about it, the teacher might very well have explained that this might be an unfair means of distributing justice, but this is what other teachers everywhere were forced to do. In which case, I could have accused the teacher of the tu quoque fallacy also. As it was, I had to justify the fact that I drew a penis on the blackboard by pointing out that others had drawn obscene things before me and were getting away with it -- I suppose this could be termed the tu quoque phallusy.

3. Survey Results.

I have sometimes lied when taking a survey, because frequently I believe that the biases of social scientists are on display in the way that questions are posed. One might compare the case of journalists -- do we actually believe that print journalists tell the truth? Do we actually believe that those who are interviewed by print journalists tell the truth? The only thing that a journalist does is to collect a number of different stories,…