and quickly developed them into his own. He learned mathematics from
Huygens and from access to Pascal’s unpublished work; from hints of Newton’s
calculus (and despite Newton’s guarded suspicion), he developed his own
version (Hall, 1980; Hofmann, 1972; DSB, 1981: 8:149–168, 10:330). Over-
lapping international networks open opportunities and generate high emo-
tional energy in the individual who takes the lead in this niche, the subjective
feeling of momentum that comes from exploiting the first-mover advantage.
Leibniz was so full of network opportunities that he hadn’t enough time
for all his projects, and many of them were left in fragments. Law, history,
diplomacy claimed his most immediate attention. He took service with the
duke of Brunswick and produced genealogical research that aided his patron
in acquiring the Duchy of Hanover, from whence the family eventually (in
1714) inherited the throne of England. When his employer’s daughter became
queen of Prussia in a dynastic marriage, he used the connection to establish
an Academy of Science in Berlin. More organizationally astute than Newton,
Leibniz founded his own journal and found patronage for new scientific acade-
mies, through which his followers—the Bernouillis, l’Hospital, and Euler—
made his mathematics dominant.
Leibniz developed his philosophy in the course of his network’s concerns.
His early training at Leipzig was scholastic, and reflections on Molina and
Suarez become his distinctive intellectual ammunition.^10 In Paris, Leibniz’s
philosophical connections were mainly with the anti-Cartesians, especially
Huet and Foucher. He also traveled to seek out Spinoza in 1676 and spent
several weeks reading his manuscripts. Leibniz became intimate with Male-
branche at the time when the latter’s famous work appeared. Soon after the
battle broke out between Malebranche and Arnauld, Leibniz developed his
own philosophy and broached it in correspondence with Arnauld, modifying
it as the result of Arnauld’s criticisms (Brown, 1984: 123; Broad, 1975).
The point of entry was that Malebranche’s occasionalism had eliminated
human free will as well as human ideas. Leibniz intervened with points from
Molina and from the scholastic tradition. Discussions in late Thomist logic
suggested the principle “in every true proposition the notion of the predicate
is included in that of the subject” (quoted in Brown, 1984: 74; Funkenstein,
1986: 98–99). All true statements about an individual person, Leibniz contin-
ues, are contained in the essence of that person, including everything he has
done and will do in the future. The individual essence is thus its own causality.
But this also means that no essence can affect another; all are causally inde-
pendent. This raises an extreme form of the problem of non-connectedness
among unlike substances, the central puzzle of the post-Cartesian field. Turning
the problem around, Leibniz notes that many true statements about an indi-
vidual appear to describe his relations with other individuals; yet each is
592 • (^) Intellectual Communities: Western Paths