historian would all do well to read what Newton himself said. The
present selection has been made with a view to the interests of all
of them. The scientist may complain that little of Newton's
mathematical demonstration is included. If he has looked into the
Principia Mathematica, he will realize that even with the notation
modernized, as in Cajori, that book is one of the most difficult of
all the scientific classics. Only a hardened reader of Great Books
would venture upon it without guidance. Newton expressed him-
self so elliptically, with such lack of concern for the ordinary
reader who could not fill in the missing steps for himself, that one
is inclined to sympathize with the non-mathematically-minded
John Locke, who, on the appearance of the Principia, was forced
to ask his mathematical friends whether Newton's demonstrations
could be relied upon, and when assured that they could, painfully
tried to puzzle out the conclusions for himself. The editors have re-
solved to appeal to readers with the mathematical competence of
Locke, who after all as a physician could claim respectability as a
scientist. Readers who demand more can turn to Cajori, or, if they
command Latin, to the earlier admirable editions of the Jesuits.

Newton was, as the phrase goes, a "seminal thinker." If we have
here been more concerned to comment on the harvest than on the
seed and its provenance, readers may exercise their own wits and
their knowledge of the history of thought on the "sources" of his
major ideas. Such an inquiry will take them far afield, and will
lead to men like William of Ockham, Francesco Patrizzi, and
Bernardino Telesio, as well as to sober scientists like Galileo. New-
ton being what he is, what started him off is of undying fascination.
But still more important is what Newton himself started. It is the
hope of the editors that those who properly appreciate what New-
ton started will be glad to learn just how he started it, by reading
his own words--often a disconcerting process with a thinker whose
originality and historical limitations have been so long buried
under the easy disguise of Newton the symbol.

JOHN HERMAN JR. RANDALL

COLUMBIA UNIVERSITY
September, 1952

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