In a sense, the AHD was a line in the sand between prescriptivists like Morris, who insist that one of a dictionary’s primary functions is to make informed distinctions between correct and incorrect uses of words, and descriptivists like Webster III’s makers, who contend that a dictionary’s function is merely to chronicle current practices. Here is Morris’s description of the prescriptivist goal for The American Heritage Dictionary: “It would faithfully record our language, the duty of any lexicographer, but would not, like so many others in these permissive times, rest there. On the contrary, it would add the essential dimension of guidance, that sensible guidance toward grace and precision, which intelligent people seek in a dictionary.” A good dictionary, he added, ought to be “a treasury of information about every aspect of words” and “an agreeable companion.”
After nearly four decades of poring over my first edition of The American Heritage Dictionary – it’s a book that invites you to read it rather than just refer to it — I can report that it has been a most agreeable companion.
—Bill Morris reviews the 5th Edition of The American Heritage Dictionary