Michelangelo drew extensively as a child, and his father placed him under the tutelage of Ghirlandaio, a respected artist of the day. After one unproductive year, Michelangelo became the student of Bertoldo di Giovanni, a sculptor employed by the Medici family. From 1490 to 1492, Michelangelo lived with the Medicis; during this time he learned from such philosophers as Ficino, Landino, Poliziano, and Savonarola. Although Michelangelo claimed that he was self-taught, one might perceive in his work the influence of such artists as Leonardo, Giotto, and Poliziano. He learned to paint and sculpt more by observation than by tutelage. Michelangelo was known to be extremely sensitive, and he combined an excess of energy with an excess of talent.