RuariMilne

You can prove something to be philosophically true or false by showing whether or not the system makes logical sense. With the example of the two people in the room and the question on initiating force, you can deduce whether or not initiating force is moral or not by applying it as an absolute rule. If you make the absolute rule that it is immoral not to initiate force, then they must initiate force in order to be moral. However only one person can initiate force, and then the other person would be reacting to that in self defence and therefore not moral. Therefore you cannot have a moral law which makes it immoral not to initiate for because then you create a system where not everyone can be moral.