Kant: A Biography

306 Kant: A Biography

His justification was that this revelation served a greater cause. Lessing
was simply more consistent than all the other rationalist thinkers, and his
intellectual honesty deserved to be acknowledged for what it was. Indeed,
Jacobi argued that Spinozism was no different from any other speculative
system; it was just more consistent. Thus "Leibniz-Wolffian philosophy
is no less fatalistic than the Spinozistic, and leads the persistent inquirer
to the foundations of the latter. Every path of demonstration issues in fa¬
talism" or Spinozism.^136 He also argued that the only alternative was faith.
Jacobi soon found himself severely criticized not just for his indiscretions
but also for his views. In particular, he was attacked as an obscurantist who
unphilosophically appealed to faith. In 1786, Thomas Wizenmann, a friend
of Jacobi's, tried to defend Jacobi, maintaining in his Die Resultate der
Jacobischen und Mendelssohnischen Philosophie von einem Frey willigen that
Mendelssohn's conception of "common sense" and Jacobi's principle of
"Glaube" were in the final analysis identical.
Kant, who followed the dispute with great interest, was encouraged by
the editor of the Berlinische Monatsschrift to intervene on Mendelssohn's
behalf— especially since Jacobi was claiming that his position was close to
Kant's.ni Kant was willing. He had already written to Herz that he had long
planned to write something about Jacobi's oddity (Grille).^138 In August 1786
he submitted his essay "What is Orientation in Thinking?" Far from simply
defending Mendelssohn against Jacobi, he used the occasion to give an¬
other introduction to his own practical philosophy.
Kant took as his point of departure Mendelssohn's heuristic principle
(or maxim) that "it is necessary to orientate oneself in speculative reason
... by means of a certain guideline which he sometimes described as
common sense... sometimes as healthy reason, and sometimes as plain
understanding,"'^39 This maxim, Kant argued, undermines not only Men¬
delssohn's own speculative metaphysics but leads to zealotry and the
complete subversion of reason. Kant agreed with Wizenmann: Jacobi's
faith and Mendelssohn's common sense amount to one and the same thing.
Kant's project was thus to save Mendelssohn from himself, as it were, and
to show against Jacobi that reason has the resources necessary for belief.
We can orient ourselves by a subjective means, namely by "the feeling of
a need which is inherent in reason itself."^140 This need of reason is two¬
fold: it is a theoretical need and a practical need. The first, already explored
in the Critique of Pure Reason, is expressed by the conditional that says, "if
we wish to pass judgement on the first causes of things, especially in the
ordering of those purposes which are actually present in the world," then