Enlightenment philosopher John Locke developed a theory of natural rights in which every free person had the rights of life, liberty, and property and that a citizen entered into government to have government help protect those rights at the expense of some freedoms.
Thomas Jefferson was heavily influenced by Locke and developed the concept of natural rights and the social contract further writing in the Declaration of Independence that every citizen had the right to life, liberty, and the pursuit of happiness.
Well think about it, Barnabas already parted from Paul. Paul didn't want to go with Mark. So that takes Paul completely off the list. So it was Barnabas and Mark who went.