The Gemara in Masechet Menahot (99b) records a discussion between Rabbi Yishmael and his nephew, Ben Dama (listen to audio recording for precise citation). Ben Dama raised the question of whether he, who had studied the entire Torah, may study Greek philosophy. Rabbi Yishmael responded by citing the verse, "This Torah scroll shall not leave your mouth, and you shall engage in it day and night" (Yehoshua 1:8). "Go find a time that is neither day nor night," Rabbi Yishmael said to his nephew, "and study Greek wisdom at that time." In other words, one is obligated to study Torah at every available opportunity, and there is thus never a time when one may excuse himself from Torah learning in order to engage in secular philosophy.
Indeed, Rav Hai Gaon (Babylonia, 969-1038), in a responsum on this subject, writes, "There is nothing better for Israel than Torah learning." One should spend his time studying the numerous different areas of Torah – Tanach, Mishna, Gemara and Poskim. The Sages say that God declared to Beneh Yisrael, "I wish they had abandoned Me but kept the Torah." Meaning, God can even accept the Jewish people’s abandonment of Him, as long as they remained devoted to Torah learning, rather than delving into philosophical queries as to whether or not He truly exists. The light of the Torah has the effect of inspiring a person toward devotion to God, and therefore this is what we should spend our time involved in.
One might, at first, question this Halacha in light of the precedent of the Rambam (Rabbi Moshe Maimonides, Spain-Egypt, 1135-1204), the great Medieval sage who was well-versed in Aristotelian philosophy. Does this not prove that the study of secular philosophy is at least permissible? The answer is that, for one thing, the Rambam delved into philosophy only after he mastered the entire corpus of Torah scholarship. Secondly, he studied this material for the purpose of formulating a response to the non-believers of his time, who denied the Torah on the basis of Greek thought. Furthermore, we cannot claim to have reached the level of spiritual greatness attained by the Rambam, such that we can be assured to emerge unscathed from the study of secular philosophy.
Therefore, we should follow the tradition of our forebears to spend our time engaged in Torah, which brings wisdom and fear of God. We should not be studying secular philosophy, which causes confusion and raises questions without providing adequate answers, thus threatening a person’s fear of God and commitment to Torah. Indeed, Hacham Ovadia Yosef writes explicitly that one should not involve himself in the study of secular philosophy.
