How little we know the true hearts and minds of our best-known heroes is admirably revealed in this new book by Messrs. Newman and Benton. The heroic biography is so often handled with mere surface understanding. Here, at last are authors who have contrived to let us see into the very heart of their subject. And a moving view it is.

How many of us have stopped to think what must have been the effect on the child Superman when his parents bundled the still damp baby into a rocket and shot him out of their lives? And did it ever occur to us that this Man of Steel, as he is frequently known, can be moved to tears by the indifference and suspiciousness of those whom he tries so hard to serve?

All this, and much more, is revealed in this book, including some truly touching vignettes of Superman reading "Little Women" to hospitalized shut-ins, or playing checkers with our senior citizens.

Of minor but sprightly interest to readers interested in Supermania will be the authors' careful description of his apartment, with red and blue upholstery predominating, the many sporting prints, the place of honor given to his stamp album and the details of his diet, which seems to consist mainly of milk and cookies.

It is heartening, too, to see the emergence into biography of these clever writers who, until this publication, had tackled nothing more serious than political satire ("Extremism"), contributions to "Esquire," columns for "Mademoiselle" and other free-lance assignments.