To the majority of people Einstein’s theory is a complete mystery. Their attitude towards Einstein is like that of Mark Twain towards the writer of a work on mathematics: here was a man who had written an entire book of which Mark could not understand a single sentence. Einstein, therefore, is great in the public eye partly because he has made revolutionary discoveries which cannot be translated into the common tongue. We stand in proper awe of a man whose thoughts move on heights far beyond our range, whose achievements can be measured only by the few who are able to follow his reasoning and challenge his conclusions. There is, however, another side to his personality. It is revealed in the addresses, letters, and occasional writings brought together in this book. These fragments form a mosaic portrait of Einstein the man. Each one is, in a sense, complete in itself; it presents his views on some aspect of progress, education, peace, war, liberty, or other problems of universal interest. Their combined effect is to demonstrate that the Einstein we can all understand is no less great than the Einstein we take on trust.