However bold the Jewish philosophers of the Middle Ages were in their research or critical in their analytic methods, they never so distrusted human reason as to deny it the power, as the Greek skeptics did, to arrive at any positive knowledge or truth.
The great problem of life, with "its righteous ones suffering woe, and its wicked ones enjoying good fortune," which puzzled the mind of Jeremiah,[4] and Moses also, according to the Rabbis,[5] and which finds striking expression in the Psalms,[6] created skeptics in Talmudic as well as in earlier times.
Elisha ben Abuyah[7] became a skeptic as a consequence of seeing a person meet with a fatal accident at the very moment when he was fulfilling the two divine commandments for the observance of which Scripture holds out the promise of a long life.
The Emunot ve-Deot was written by Saadia, as he says in the preface, because of the many doubters who were to be convinced of the truth; and Maimonides, in the introduction to his Moreh, states that he wrote that work as a guide for those perplexed by doubt.
A remarkable type of skeptic was produced by the sixteenth century in Uriel Acosta, who, amidst a life of restless searching after truth, denied the immortality of the soul and the divine revelation.
Another such was Leon of Modena, who, complaining that "the thinker is tortured by doubt, whereas the blind believer enjoys peace of mind, and bliss in the world to come" (see Ari Nohem, quoted by H. Grätz, Gesch.
130), arrived through skepticism at a liberal interpretation of traditional Judaism (see S. Stern, Der Kampf des Rabbiners Gegen den Talmud im xviii.
Likewise, serious Jewish encounters with the Greek sources of philosophical scepticism (i.e. disbelief that a true knowledge of things is attainable by humans) are rare until thinkers like Simone Luzzatto in the early-modern period, although a weaker definition of scepticism (i.e. doubts about authority and suspension of judgment in approaching sources of knowledge, whether secular or sacred) might be said to have a Jewish legacy from the time of the first-century philosopher Philo onwards, including tantalizing figures such as Elisha Ben Abuyah in the Talmud, and especially in the form of medieval fideism (i.e. the idea that faith is independent of reason).
These shallow intellectual eddies of pre-modern doubt about God’s existence and nature, and about the veracity of human knowledge derived through tradition, became stronger currents with the seventeenth-century philosopher Spinoza, who was regarded by many as atheistic, and with the eighteenth-century Jewish Enlightenment or Haskalah.
It was from that time that a good number of Jewish thinkers felt obliged to establish oppositional, alternative, synthetic, or complementary models explicitly relating Judaism to the challenges of such atheistic and materialistic philosophies.
There is, however, a short entry for ‘atheism’ in the Jewish Encyclopedia, its inclusion being best explained by the idiosyncratic philosophical and interfaith interests of the authors, the Reform rabbis Emil G. Hirsch and Kaufmann Kohler.