Isaac Ibn Ghiyath
Isaac ben Judah Ibn Ghiyath was a leader of Andalusi Jewry and an accomplished poet, halakhist, and exegete. The descendant of an old Jewish family of Lucena, a Spanish city with a large Jewish population at the time, Ibn Ghiyath came to head the academy there after the death of Isaac al-Fāsī (Rif) and wrote a treatise on the laws of the festivals as well as a commentary on the Talmud. His piyyutim, which incorporate scientific and philosophical concepts, were significant early steps toward the use of Hebrew for scientific writing. His halakhic writings drew from both geonic and Andalusi authorities, particularly Samuel ha-Nagid (993–1056).