Philosophy vs. Prophecy
According to my understanding, philosophy addresses a lot of the questions that Judaism does, so what advantage does Judaism have over philosophy?
Rabbi Yehuda HaLevi addresses your question very directly and cogently in his work The Kuzari that was written in 11th century Spain. The book is an embellishment of a discourse that purportedly took place between a truth seeking pagan ruler of the Kuzar nation (somewhere in central Asia) and various religious leaders – including a rabbi. Your question is one of the fundamental questions raised by the leader and answered by the rabbi in a dialogue that results in the Kuzar’s decision to convert his kingdom to Judaism.
The rabbi makes the following four arguments in favor of prophecy over philosophy:
Philosophy is purely intellectual investigation originating in the mind of a human being in his effort to comprehend matters largely outside himself. Since the process is directed from below toward subjects on high, the level of understanding is, by definition, limited and finite. Revelation, however, insofar as it describes the infusion of truth from Above into the human intellect below, will necessarily reveal truths otherwise occluded by mere intellect alone.
Philosophy is nothing more than speculation. Since its conclusions are based on the guidelines of instruction in formal logic, analysis, technical terms and mechanical concepts, they are not inherently intuitive or correct. Prophecy, however, is a purely fluid and natural result of spiritual refinement through which, with the grace of G-d, a person becomes privy to existential truths which kindle his soul and intuitively spark inspiration in the hearts and minds of others.
Rarely does one find agreement between philosophers in their views of the supernatural. Even in the physical realm there is often disagreement among them. When they are in accord, it is not because they empirically arrived at the same results but rather because they adhere to the same philosophical school. Prophets, however, despite experiencing revelation in different venues and visions, are seeing essentially the same thing and sharing and disseminating the same message.
Considering their conduct, their knowledge, their ostensible search for truth and their exalted purpose, one might expect that the gift of prophecy would be quite common among the philosophers, and that tales of wonders and miracles would be related about them. However, we find the opposite to be so: true visions are granted to those who pursue truth through spiritual refinement, while those who strive after speculation never attain true prophetic vision. This proves that there is a secret to the Divine Influence that cannot be fathomed by the study of philosophy, nor is it revealed to philosophers.
- The Metzuda Kuzari pp. 3-12.