Schleiden, Matthias Jakob, << SHLY duhn, mah TEE ahs YAH kawp, >> (1804-1881), a German scientist, showed that all plants are made of cells. Schleiden established plant chemistry and the plant cell as the basis of botany (the study of plants). Before Schleiden, botany focused mainly on the forms of plants, often relying on dried specimens. Schleiden urged scientists to study live plants using microscopes. He insisted that plants could only be understood at the cellular level.
Schleiden cared deeply about scientific methods. He argued that scientific studies should be based on careful, systematic observation. However, Schleiden rejected the argument that life can be explained by physical and chemical laws alone. In highly successful popular science lectures and books, he discussed a great variety of topics, including medieval Jewish culture, salt, and sound, among others.
Schleiden was born in Hamburg, now part of Germany, on April 5, 1804. He studied law, opening a practice in 1826. However, his profession made him so unhappy that in 1831, he attempted suicide. In 1833, he began to study botany, sharing ideas with fellow German scientist Theodor Schwann. Schleiden inspired Schwann to demonstrate that animals are also made of cells. Schleiden performed his most significant plant studies between 1838 and 1842. His most important book was Principles of Scientific Botany (1842-1843). After 1842, he concentrated on popular works and debates about scientific methods. He died on June 23, 1881.
See also Schwann, Theodor.
