Click here for home,

The Value Of Surplus Information

Brian D. Rude 1974

      Surplus information is simply more information than is absolutely necessary in a given situation. My thesis is that there are very good reasons to supply surplus information in many varied situations. I will give an example.

      I got a call rather late one night from a woman who rents a house from us. She thought the furnace wasn't working right. The blower kept going long after the flame stopped and she thought this meant something was wrong. I had to explain to her that this was the way it should be. I could have simply said, "No, it's okay. There's nothing wrong with the furnace." This would have been a perfectly true answer, but it wouldn't have been a very satisfactory answer. Strictly speaking I told her all she needed to know, but it wouldn't have set her mind at ease. I could have gone one step further than this. I could have said, "Well it's okay, because a lot of furnaces do that." This tells her a little bit more. It gives her some indication that I am not just making excuses, that I have actually considered the problem as she described it. Still it's hardly an answer to set her mind at ease. I could go several steps further. Consider the following possible answers:

      3rd answer - All furnaces do that. Our furnace in this house may start and stop the blower several times after the flame cuts out. Your furnace is just doing the same thing.

      4th answer - All furnaces do that. Our furnace in this house may start and stop the blower several times after the flame cuts out. Your furnace is just doing the same thing. It's not making any screeching noises or smoking or anything is it? That's what would really mean trouble.

      5th answer - All furnaces do that. Etc, etc, . . . . . You see there's a separate thermostat inside the furnace that controls the motor. The thermostat on the wall that you set controls the flame, but not the motor. When the inside of the furnace gets hot enough, maybe 150 degrees or so, then this other thermostat starts up the motor to distribute the heat through the house. When the flame cuts out the walls of the furnace are still hot so the motor keeps going until it cools down. So the motor keeps going for a while after the flame stops.

      6th answer - All furnaces do that. Etc, etc, etc, etc, etc . . . . . Now the motor may not be set quite right if it keeps going for so long. I'll adjust it the next time I'm over there.

      Each of these answer is more complete than the last. Each answer conveys the same basic point - the furnace is doing what it should do. But there is a world of difference in the psychological effects of these different answers. Answer one is just asking for trouble. The obvious implication to be gleaned from this information is that I do not respect the woman's concern about the furnace and I don't want to be bothered. There is no reason for her to trust this answer.

      Answer three is considerably better. Here I at least acknowledge that I understand the problem. Yet still I am giving only my word that the furnace is okay. She has no way to check it out. What is she to think if the next day a friend of hers says, "He's feeding you a line. The motor and the flame are supposed to work together."? She has no way to check out either my answer or her friend's statement. She certainly has good reason to doubt that my answer is entirely satisfactory.

      The fifth and sixth answers give her some way to check out my answer. When her friend says the flame and blower are supposed to work together she can reason that that would be a less efficient way for the furnace to operate than the way I described. My answer makes sense whereas her friend's answer has only her friend's affirmation as to its accuracy. Answer number six has the further advantage of confirming my intention to keep things running right. So of course answer six is the answer I gave, not verbatim perhaps, but in content. Could a social engineer do any less?

      I mentioned that the advantage of surplus information in this situation is the goodwill that it generates. This is true, but in a larger sense the advantage is perspective. The goodwill ensues because I gave the woman a perspective on the problem. This perspective set her mind at ease.

      This next example also illustrates this advantage of perspective. This is from an article by Evan Hill in the Oct. 73 Readers' Digest. His article was on the advantage of accuracy.

      Accuracy can never be overdone. A magazine editor once asked me if I knew a certain famous man who needed help with his writing.
      "Yes, I know him", I said. "But I'm not sure he knows me. I have visited with him at least six times, and each time he needs to be introduced to me."
      The editor exchanged a look with a colleague. "We asked", he said, "because you had told us you knew him, but when we telephoned him, he said he'd never heard of you. Now we understand." And I got the assignment.

      The point of Mr. Hill's article is the importance of accuracy. However strictly speaking I would say that ,"yes, I know the man" is a perfectly accurate answer. Fortunately he had the initiative to give more than accuracy. He gave a bit of surplus information - "But I'm not sure he knows me . . . ", and this information made a great difference. It gave his editor the perspective to really know what was going on.

      Having a perspective allows a person to adjust his actions to changing circumstances. Once when I was a coolie in the Army a sergeant told me to go over to the PX and get him a hot dog and a coke. When I got there they were out of hot dogs, so what was I to do? The sergeant told me everything I needed to know, so he thought. But he gave me no contingency instructions. Do I bring him just the coke or do I bring him nothing at all? This is a situation in which everyone who gets stuck with running errands comes up against now and then. I can't really say that contingency instructions should be given in such situations, but it does illustrate the disadvantage of having only "essential" information.

      Surplus information provides automatic contingency instructions. An auto mechanic who knows only tune up procedures is stuck when the brakes go out. A pharmacist who knows only how to fill prescriptions is stuck when he gets a batch of pills that smell funny. A consumer who knows only how to figure price per pound or ounce is stuck when confronted with a can containing 400 grams of beans.

      Part of the advantage of perspective is the confirmation it brings. Confirmation here just means extra knowledge that assures one that the information he gets is accurate, that he is doing the right thing, that he is on the right track. An example of this would be in giving directions. If I ask a passerby how to get somewhere and he tells me "six blocks west, two blocks north, then three blocks east", then he has given me essential information. But if he tells me in addition that I'll go across a bridge, by a big hospital, and through a park, surplus information in other words, then I get confirmation that I am on the right track as I go along. This confirmation is very welcome when one is anxious about arriving on time.

      Confirmation is a mass of supporting knowledge. When no supporting information is given then sometimes erroneous assumptions are made. I heard a good example of this. I regret I cannot cite the source of this example. It seems a manufacturer kept getting contaminated material, contaminated by body oils from somebody's hands. A worker kept forgetting to use his gloves even though his boss had told him a number of times to do so. Finally the worker told the boss, "I don't need gloves. This stuff doesn't hurt my hands at all!" The boss had told the worker everything he needed to know, "Use your gloves", but nothing more. The worker had then assumed the gloves were for his protection and therefore felt free to forget about them. Had the boss supplied just a bit of surplus information, " . . . so your hands won't contaminate the stuff," then the worker would have worn his gloves right from the start.

      A general education is mostly surplus information. Knowing history and literature doesn't usually help a person hold a job and earn a living. Yet as a society we still believe in the worth of a broad, as well as a specialized, education. One advantage of a broad education is that it prepares us to meet contingencies that are impossible to foresee. Another advantage is that it provides a supporting framework, confirmation, of the more specialized education that is more immediately relevant. Both of these advantages are part of what I mean by perspective.

      Information is valuable. It often comes at high cost. Therefore it might seem that surplus information is giving away something valuable that should be conserved. Once in a while this is the case, but usually it is not. Most information in our everyday lives can be freely shared without diminishing its value, and it is usually to everyone's profit to have it freely shared. Also, if information is valuable, some thought should be given to the eliciting of information from others. This is one very important advantage of surplus information. It elicits surplus information in return.

      I have found this especially valuable in buying. If I'm looking at a refrigerator in Wards I'll casually mention the refrigerator I just looked at in Sears. This invites a comparison, which is valuable information to me. While looking at a car the other day I mentioned to the salesman that another car dealer had a real attractive deal on low mileage cars that had been leased to the post office. This gave the salesman an opportunity to tell me what might be wrong with such a deal, something the previous salesman would not like to mention. The second salesman's silence indicated that perhaps the deal might be pretty good.

      It should be pointed out that such an approach might elicit more than a free flow of information. It might be taken as a challenge to the salesman, or as an affront. It might elicit a hard sell or a defensive reaction, neither of which I want. Therefore I try to be careful, to talk casually as I examine the product. The salesman can then either offer comments or ignore my words as he chooses.

      Another example of surplus information eliciting more information is seen in rumors. In a stable social institution where interpersonal interaction abounds, such as in most schools, surplus information flows freely. Thus news that the senior prom queen has been seeing a sailor from Newport News, or that the basketball coach can't handle his money, travels quickly. Such things are not essential information. No one has a "need to know" such information. The information just flows.

      We generally think of rumors as bad things, irresponsible and malicious. Often this is the case. However gossip is also a very strong spice of life. I wouldn't want to do without it altogether.

      So far I have talked as if surplus information were all good and no bad. Of course this is not the case. There are some very real disadvantages to surplus information in some situations.

      Rather than providing confirmation, surplus information may only cause confusion. In the example of giving directions I could be thoroughly confused if my informant tells me, Well you go up this road to the first traffic light, well actually it's not the first but the first one is only a walk light and it's always on, so then when you get there, it's six blocks, as the crow flies, but actually one of these blocks is a double block, you're okay if you count streets but don't count house numbers, now where was I, oh yes, then turn right . . . . . . . ." By the time my informant is finished I have lost the essential information.

      Another disadvantage of surplus information is that it makes it harder to lie As a general rule this may be good, but there definitely are times when lying is the decent thing to do. If I tell my wife I like her green dress and then tell a neighbor I hate anything in green, then I may be in for trouble. Ideally we should have nothing to hide, but being human as we are, there are times when surplus information can do us wrong. We want our privacy, and surplus information can sometimes be a violation of this privacy.

      Another problem is that surplus information can often be confused with redundant information. It does little good to repeat the same thing a number of times. And it can be very aggravating.

      Even more seriously, surplus information can displace essential information. As a teacher I learned that if a kid comes to me and says, "Is this right?", he wants to know exactly that. He wants a yes or no answer. If I reply, "Well, Johnny, you see the basic principle involved here is . . . . . .", then I am most likely to turn him off. So first I say, "Yes, that's the way you do it", or "No, you must have a mistake somewhere here". Then having acquired the essential information, in no uncertain terms, he will be receptive to other information.

      So there are both advantages and disadvantages to surplus information. In general I would say the advantages outweigh the disadvantages. However each situation must be judged by itself. Only experience can tell just how much surplus information is appropriate in a given situation. I think an awareness of the idea can be a valuable help to experience.