  Like so many intellectuals who came of age in the 1780s, the young Rehberg's intellectual landscape was formed by the pantheism controversy.  This controversy began in 1785 when Friedrich Heinrich Jacobi proclaimed in his Briefe über die Lehre von Spinoza to a stunned public that Lessing had been a Spinozist.  Jacobi used this juicy bit of gossip to make a provocative philosophical point: that all rational enquiry, of which Lessing was such a eminent exemplar, ends in the atheism and fatalism of Spinozism.  The only way to save oneself from such atheism and fatalism, Jacobi suggested, was to take a “salto mortale”, a leap of faith in a personal God and freedom.  Hence Jacobi presented his contemporaries with a dilemma: either a rational atheism and a-moralism or an irrational theism and morality.  There could be no comfortable middle path: rational demonstrations of the essential beliefs of morality and religion.  Jacobi's dilemma was a profound challenge to the German Enlightenment or Aufklärung, whose ultimate article of faith was that there must be some rational foundation for our moral and religious beliefs.  The effect of Jacobi's book on the German intellectual stage was like “a bombshell”.  Within the next year, Kant, Fichte, Herder, Reinhold and Mendelssohn would write responses to it.  Virtually every young romantic—Friedrich Schlegel, Novalis, Hölderlin and Schleiermacher—would take a stand in the ensuing debate.