Socially shared knowledge is not something we are taught in school or read in books. Its foundations are in the routine necessities, the social interactions, the problems, dangers, and enjoyments of everyday life.
Over the course of a lifetime we acquire a set of recipes: techniques for dealing with frequently arising situations. Our practical knowledge includes such specific information as how to scramble eggs; how to administer first aid; how to deal with drunks, men and women, bores; which snakes and spiders are poisonous; and why we shouldn’t eat refrozen meat.
Every adult has a huge stock of knowledge, most of it held in common with others. It comes from the usual sources: television, radio, magazines, newspapers, advertisements, parents, schooling. This is the common-sense knowledge of the man in the street. What you know is personalized by the first-hand encounters in which it was acquired — the people you’ve known, the places you’ve been, the jobs you’ve held. But even these experiences are overwhelmingly common, shared by most people with only minor variation.
Your personal stock of knowledge reflects your personal reality: the recurrent events; the patterns of a typical day, week or year; the probability texture of your life. It tells you what to expect (the car won’t start), how likely this is (only when it rains), and what you usually do about it (wipe the plugs). For the most part, daily life is a succession of repetitive, predictable situations in which the details might as well be identical.
Although not an overstatement, this is not meant to be depressing. Most of life is routine. The basic sequence of events is recurrent and familiar and requires nothing more from us than habitual, automatic cooperation. But this prison of dull similarity actually works to our advantage. It leaves us free from the need to think of these things.
All situations were originally novel — there’s a first time for everything. We have to learn how to eat, how to walk, how to write, drive, smoke, have sex, and deal with subordinates and superiors. A new situation presents us with a question, a "problem": How shall I do this? You have to stop and think: Shall I shave with a blade or an electric razor, take a bath or a shower, take the car or a train?
Every routine represents a situation that was originally new and open, but that is now definitively closed. We have either selected a permanent, automatic mode of behavior (blades, baths, and car), or at least narrowed the options (coffee or tea).
One of the things we know, however, is that a routine can once again become open to change. All routines, as with all knowledge, are only valid until further notice. If I lose my right arm, I’ll have to learn to write with my left hand. In a blackout, I have to invent alternatives for all routines that require electricity. It’s when our recipes no longer apply that we have to modify them.
Minor improvements are usually incorporated into our routines by accident and luck, not by premeditated intention. Routines only come to our attention when they are disrupted. The store is out of brand X so you try another and discover that it really is better. The main street is closed and you find the detour is a better route. New solutions become new routines. In this way our knowledge expands, changes, and reconsolidates itself.
While the "final" solutions that make up our routines bear a stamp of individuality, both our problems and their solutions have for the most part been acquired through imitation and adaptation. Recipe knowledge is socially established and transmitted. It represents options that have already "worked for others."
The use of shampoo, deodorant, and toothpaste, what to eat, how to cook it, what to wear, how to clean a house, the movies we see, the television shows we watch, the candidates we vote for — what we do in these situations is determined by the products available and what we believe other people are doing. Public opinion polls tell us what others are thinking. Advertising brings to our attention problems we may have been unaware of, primarily problems of boredom, sex, and leisure — the failure to keep pace with fashion.
Commercial products offer devices for use in the socially established routines of a particular culture. These products do more than simply offer direction and advice; they designate and define the problems and needs they are designed to meet — no fun, dull meals, limp and lifeless hair. Behind all solutions, behind all advice, lie the assumptions of what the "problems" are. And behind that is the implication of what the routine should be. If attention is devoted only to competition among solutions, the reality of the problem itself doesn’t easily get called into question.