Plato, one of the famous philosophers of our time, tried to define the value of justice in his writing. In Republic, books one through four, Plato writes about a conversation Socrates and Thrasymachus' had discussing justice. While Thrasymachus' claims that injustice is more preferable to justice, Socrates tries to counter is claim through a series of five acceptable facts.
The first acceptable fact says "Every X has a specific function." True, if X did not have a function, it would not exist or have a name. If we argue that every X has a specific function then we can say that the functions were teleologically determined. Man-made things are made to carry out a certain function that the man decides (a watch to tell time), and even though man decides its function, they decide the objects teleological function. It can also be assumed that the first fact in Plato's function argument is suggesting that every X has only one function. To counter this, one can also say that a certain object can have more than one function. For example, leather's primary function is to be the skin of an animal but it can also, be shoes, clothes, bags, or water bottles. Likewise, one can conclude that the first fact is correct but would sound more accurate if it was phrased "Every X has some or one specific function."
Socrates' next acceptable fact in his argument is "The virtue of every X allows it to perform its function well." Again this fact is implying that there is only one function every X can do well. Continuing on the leather example, of the many functions of the material, its best and primary function is to be the skin of an animal. Of course, when leather is made into objects we may say that it's best when it's made into clothing. For instance, leather shoes as oppose to plastic shoes perform their function well because they last longer. Another example is of a doctor and a pharmacist. Although doctors have been trained to make some medicines they are not experts at it, where as pharmacists have been trained to do just that-make medicines. Because of the kind of virtue or training they have, not only does it allow them to perform their function, but to perform it well.
Moving on, Plato goes to say that "The human soul has a specific function-to live," or to choose. Consequently, every moment of a human's life they are thinking what they should do to better their life? 'What will make me feel good right now, coffee or tea?' Human instincts, to run or to sleep or to dodge hard situations, are all meant for one thing-to live or to exist. In any harsh situations their aim is to over come and solve the problem to keep living. For example, your profession is chosen by you because it makes you happy. These decisions you make now to keep living give you other chances to make other decisions to living more. The process goes on and on. To make the choice to be a doctor, you have to choose what the best school is and once you get your degree where you will work? Once the money starts coming in, what will you do with it? As one can see, each decision leads to a decision to make another. If the human soul's specific function is to live or choose, this example of becoming a doctor greatly illustrates this acceptable fact in Plato's argument.
Closely related to the last acceptable fact, the next one says "The virtue of a human soul allows that human being to live well." This means that if every decision one makes is to make another, the other decision they expect to make is for something bigger and grander. Of course, everyone has their own definition of living well. To me, living well would be to have a comfortable home where I can fulfill my duties as a daughter, sister, mother, and wife with ease and no hiccups. Also, living well is to see my family happy and to help them in anyway possible without much difficulty; financially being able to meet anything that comes my way. In addition, then comes the topic of elegance. Would I care if my glass of water was made of real crystal with fifty six percent lead or that it was plain old glass? Would I care that the water inside the glass was pure or not? Although quality of life and living well go hand in hand the virtue of the human soul allows them to make the decisions to have that life, however they may define it.
"Justice is the proper virtue of the human soul." This part of the function is out of the blue and without anything bolstering it. How do we know that justice is the virtue and not something else? This fact is also implying that humans are born with this virtue...that humans are born with the sense of justice in them. When justice is finally defined in the 4th book of The Republic it says that justice is the 'proper ordering of parts,' that justice is the harmonious order. My question is what is harmonious to you? People have different views of harmony, different view on how to live life or what is right and wrong. For example, in the story Gulliver's Travels, Gulliver, an explorer, comes across a savage race (in his opinion) he calls the "Yahoos." The Yahoos are a tribe that rarely dress and eat uncooked meat but still they are happy in their ways of living for they have not make an effort to change. We may call their dress style poor and their food nasty but they may consider themselves elite. In this example, Justice is more an opinion then fact which varies among people. People value Justice in their own way and find ways for it to fit their lifestyle. Furthermore, if the Yahoos and our kind co-existed, there would be a conflict because of our differing views of justice an injustice. If this happened, hypothetically, we would have to come to a compromise where we both redefine our justice system to fit our situations. With relation to redefining the system, if justice can be changed so fast is it really a virtue of the human soul? Despite that I do not completely agree with Socrates that justice is the virtue of the human soul, we can take this as a presumption to explain the rest of the argument.
Considering the presumption above, the next acceptable fact says that a "just soul allows a human being to live well." In addition, a just soul must be a person who has the perspective of good and bad and has been taught to tell the difference. Moreover, they should be someone who has been warned of the dangers of injustice. This warned and just soul allows a person to live well. Why live well? Because the person knows what is right and wrong and will make choices in the direction of gaining something good. And if Justice has been planted in their brain then the person will only make decisions to get good thus, be good.
If a person is just and they know justice then the last phrase "No one would prefer to live badly over living well" is obvious. If justice has been planted into the brain and the function of a human is to live well and justice is the virtue of the human soul then this person has no way they would want to live badly. If a person has never been taught to blow bubbles because it was bad, no one would be taught to do it, hence blowing bubbles would not exist. Clearly, if one is taught to do something the right way all their life, they will continue to only go the right way.
Through a series of acceptable facts and deductive reasoning Socrates comes to a conclusion that justice is preferred over injustice. If justice is good living and living good is in the human soul then injustice will not be preferred over justice. We were never taught to get injustice but to always run away from it to justice-getting the good world and avoiding the bad.