1. A text comprehension and retrieval method for identifying text words presenting concepts in a computer coded document related to the concepts presented in a computer coded expression of query words, comprising the steps of: calculating a first letter-semantic value for each of the query words by comparing each of the query words to itself; calculating a plurality of second letter-semantic values for each of the text words in a plurality of blocks of text of dynamically predetermined size by comparing each of the query words to each of the text words in each of said blocks; identifying the text words of the one of said blocks having second letter-semantic values that compare most closely to said first letter-semantic values.