Owning Thoughts

Recently a friend was talking about not understanding the blindness of a certain group of people and their viewpoints. Wondering why thinking people thought the things they did. And why she couldn't get it; wondering what they saw that she didn't. My response was that when one's parents, grandparents, great-grandparents, etc. espouse certain views, you develop a way of thinking that is difficult to change even when you want to. Where do our thoughts and the thoughts of our "great cloud of witnesses" begin and end? Which of our thoughts do we own? Which ones belong to our friends, our family, our co-workers, the authors we read? How much of what we think rises from within? How much from without? Are they a collage of all we've ever learned? A composite whole of who we are that changes daily, hourly as we imbibe from life's chalice.