We need to be able to solve a great number of problems that are very hard to understand. One way in which we can build an understanding of these is through analogy. There are situations in which analogies can be a powerful way of building an accurate conceptual model of a problem or system. They can help provide the ingenuity necessary to solve today's difficult problems. However, analogies can be themselves problematic, even harmful. There may also be things so intangible that they are beyond human understanding.
From the Un-Distinguished Lecture Series (http://ws.cs.ubc.ca/~udls/). The talk was given Jun. 13, 2008.