This past weekend, I was discussing the nature of explanations with some relatives. I argued that to explain anything completely, one would have to explain absolutely everything, given the need for context in a complete explanation and given the inter-connectedness of all that we know. Many explanations falling short of explaining everything work, at least on a local level, because on a local/pragmatic level an explanation is merely a description that makes us feel good. Today, I came across a quote by Carl Sagan that relates to the above: