Thomas Jefferson's Declaration of Independence

Thomas Jefferson's Declaration of Independence is his version of what an 'Ideal Society' would be and relies on the argument (correct me if I am wrong) that since the King did not follow the rules that governed society and was now a cause to create new rules.
Now what I am trying to understand is, lets say I am a 'Relativist' (someone who believes there is no 'ideal society') and I meet up with Thomas Jefferson an I decide to 'challenge' is argument of an 'ideal society' - the problem I am having is that I need to challenge him on his argument and not on the description of the society. How could this be done?