Question: In terms of Crito and Apology in a society formed by social contract, is it possible to oppose any given law as unjust without appeal to divine law?
1) In Crito Socrates draws a link between an obvious understanding of what is best for physical training (natural training) and what is best for training in the virtues (intellectual or spiritual training). This leads me to think that if one is willing and able to consider the matters humbly and honestly, the way forward towards increased justice will be as self-evident as the way forward in physical training. Both will enable one to live a good life, though the life of the soul is of far more importance than the life of the body.
2) Socrates states that majority opinion does not equate to a good opinion (good is equated with wise and just according to Plato). Greek city-states varied in the goodness of their laws and common life. For example, the city of Thessaly is regarded by Socrates as being disordered. One does not need to appeal to divine law to recognize that a disordered city has disordered laws which result in a disordered common and individual life. Socrates states that ‘virtue and justice are man’s most valuable possessions, along with law and lawful conduct’ and that moving to a city like Thessaly would be a shameless association with people who care little if at all for such valued possessions. The life of the mind has been regarded as more important than the pursuit of wealth by philosophers without appeal to Divine Law (e.g, the Stoics, if I understand them correctly).
3) In Apology Socrates states that his purpose within Athens is to be a gadfly which wakes and harasses the citizens to spur them on to consider their lives and priorities. People have an obligation to try and persuade the city in which they’ve chosen to live, regarding the justness of its laws. To be ‘satisfied’ to live in a city is not the same thing as to think the city is perfectly just. While some laws may well be concerned with questions of ultimate truth, others will be more practical in nature. Socrates is being tried not because he claims to know fully what justice means, but rather that he is pursuing knowledge of justice without regard to the opinion of others or personal safety, and he seeks this knowledge from anyone who claims to possess it. He does not criticize his treatment in reference to divine law, but rather regarding what is best and most healthy for the city, namely that they encourage and embrace the pursuit of wisdom and justice, and that they celebrate someone like him who is called to further this pursuit. It is possible to oppose an unjust law in terms of how it impedes the growth of knowledge of what is just, even if there is no certain understanding of what is perfectly just in every circumstance.
Personally, I do not believe that it is right (or even possible, in a coherent way) to fragment what is imperfectly just in even the most insignificant matter from what is ultimately wholly just in terms of Divine Law. However, on a basic and natural level, we may approach a given set of laws using our God-given reason which is available to every human being capable of thinking (e.g., the principle of non-contradiction) and discern between degrees of justness. We simply aren’t able to comprehend Divine Law fully, so we pursue it as best we can through nature and revelation. A natural and rational approach to the law may serve as a sort of ladder upon which we climb towards the higher and more pure intellectual and spiritual apprehension of Divine Law which we will only be able to understand by way of Divine grace.
Mind your Maker 