Phenomena are hierarchical: all things cannot be understood by considering only waht transpires on a single rung. No matter how well I understand the way a transistor works, I will not be able to deduce from this knowledge why my computer crashes. If I sow seeds that fail to grow, I will do better to begin by thinking about the nurient content, humidity, and temperature of my soil than by performing a genetic analysis of the seeds. Much of the skill in doing science resides in knowing where in the hierarchy you are looking - and, as a consequence, what is relevant and what is not. (查看原文)
