- Sodium (Wikipedia)
Sodium is the chemical element with the symbol Na (from Latin natrium) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth’s crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth’s minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans.
- Zeno of Citium (Wikipedia)
Zeno of Citium (/ˈziːnoʊ/; Koinē Greek: Ζήνων ὁ Κιτιεύς, Zēnōn ho Kitieus; c. 334 – c. 262 BC) was a Hellenistic philosopher from Citium (Κίτιον, Kition), Cyprus. He was the founder of the Stoic school of philosophy, which he taught in Athens from about 300 BC. Based on the moral ideas of the Cynics, Stoicism laid great emphasis on goodness and peace of mind gained from living a life of virtue in accordance with nature. It proved very popular, and flourished as one of the major schools of philosophy from the Hellenistic period through to the Roman era, and enjoyed revivals in the Renaissance as Neostoicism and in the current era as Modern Stoicism.