Important figures are: Philo of Alexandria, Daud al-Muqammas, Isaac Israeli, Al-Fayyumi Saadiah Gaon, Solomon ibn Gabirol, Abraham ibn Ezra, Abu ’l-Barakat al-Baghdadi, Abraham bar Hayya, Abraham ibn Daud, Moses Maimonides (the greatest one), Shem Tov ibn Falaquera, Judah ben Moses of Rome, Levi ben Gershom, Hasdai Crescas, Benedict de Spinoza (the most important of the modern period), Moses Mendelssohn, Hermann Cohen, Franz Rosenzweig, Martin Buber, Abraham Joshua Heschel, Yeshayahu Leibowitz and Isaiah Berlin.