Locke in Relation to Politics

As I was reading through Locke, I was reminded of a conversation I had with Professor Graban during office hours about politics. We spoke of speaking to others who had differing politics beliefs and trying to understand them. Professor Graban said often she asked for definitions from people in order to better understand their political stance. I can now see the roots of that after reading Locke's essay. We have very different opinions of what life, liberty, justice, taxes (the list goes on) really mean. Keeping in mind that, "the idea which each stands for must be learned and retained" means that each of us has come to learn and view these concepts in very different ways (Locke 218). These concepts become even more complicated when knowing that, "nobody [has] an authority to establish the precise signification of words, nor determine to what ideas any one shall annex them" (819). How can I say that someone who believes "life", or a life with the rights of a person, covers the "life" of a fetus? How can I really say their position is unjustified? I happen to be pro-choice, but perhaps that's because I have a different conception of the word "life", not to say that a fetus is not alive (I mean, it does have a heartbeat). Keeping this potential difference in the defintions of words in mind, I think it'll be easier to understand or at least realize the differences we all have in our political stances.