Ayn Rand taught our natural rights are such that ‘I am free to pursue my own happiness provided that pursuit does not encroach on the rights of others’. It is difficult to argue such a point intelligently or perhaps rationally and it lays the grounds for that which a governing body may or may not enforce rule over.
The crux of this understanding is that we are all born here, and we have not yet found an undeniable purpose for our existence, if there can ever said to be one. Without such instructions or a foundation for logic and rule of law, there is left the difficultly of finding or optimizing social order.
In other words we are all here, and we must either get along or not, and it cannot be otherwise easily argued that one group should have control of another groups freedoms without good reason.
What is good reason?
Some of the greats successfully argued that SOME law and governance is needed to allow for the greatest possible freedoms for the general or average individual man.
Locke argued that governance then should be founded on the principle of least authority. Essentially the only valid governance is governance that NECESSARILY encroaches on the peoples rights, to ensure a greater freedom.
Now, what laws are necessary? This is the great dialogue. It is the crux of how modern society was formed and evolved.
The great evolutionary progress in relation to technology. The advent of a technology may render the security or purpose provided by a certain law unnecessary, then society must or should adjust accordingly.