In life, often it is necessary to solve the problem of choice. As a rule, the choice is made on the basis of some criterion. On this subject there is even an old parable about the Buridan donkey. Once near him, at the same distance, two arms of hay were placed at the same time. I thought the donkey, I thought how to start with such arms, and so I did not come up with anything - I died of hunger. Why? The mathematician would answer this: "because the donkey did not have a criterion of choice..."

Similar tasks of choice: what is better, what is worse, what to do first, and then what we do is perfectly fine, we, none of us die of hunger only because it does not know which dish is for the first and which for the second. Hence, we have some selection criteria. Therefore, the real, and not the fairy-tale long-eared in such a situation, certainly would not remain hungry.

What exactly are these criteria? Yes the most different. They can be not only the most diverse, but also with the passage of time to change rapidly depending on some external causes. What seems possible today is impossible tomorrow. For example, on Monday Petya ate six portions of ice cream instead of dinner, because he loves ice cream more than anything else. And on Tuesday at dinner he ate a soup, then a cutlet and washed it down with compote. Why? Had he stopped loving ice cream? No, just on Tuesday at home there was a mother who did not allow him to eat one ice cream. And it's good, when among the set of criteria we can immediately single out a single one - the main one, whose requirements we have to obey in the first place. For example, Vitya received a task from the teacher to choose from a bunch of twigs those, whose length exceeds 20 centimeters. Here everything is clear: take from the armful of twigs, compare them with the ruler-standard and sort according to the length.

But in practice, such simple, one-choice problems of choice do not occur very often. Much more often, multicriteria, complex problems are encountered, the number of choices in which amounts to several tens, hundreds or even thousands. Take, for example, the task that sooner or later one has to solve for everyone - the task of choosing a profession. To date, there are tens of thousands of different professions on the globe. Which of them is right for you? .. Then you will involuntarily think about it and begin to sort out what is more important: a good salary or an interesting creative work? Do I need to graduate from university or enough and vocational schools? What are the prospects for growth? Does this profession give you the opportunity to travel around the world to light or spend all your life in one place?..

And to solve this problem is not easy! Sometimes, a person will replace more than one profession, until he finds his own. A change of professions is not only your loss in earnings. This is the loss of the state: again you need to teach a person, wait until he gains the necessary experience, will begin to work in full force... And all this has a strong impact on the economy of the enterprise, industry, country...

Economists were the first to pay attention to the problems of choosing such a plan. They began to analyze the methods by which a person makes a decision, began to write these methods in the form of some axioms or theorems. So gradually, a new direction in science - system analysis - began to take shape.