Structure of the Earth obducted onto the continental crust and preserved as ophiolite sequences. Many rocks now making up Earth's crust formed less than 100 million (1) years ago; however, the oldest known mineral grains are about 4.4 billion (4.4) years old, indicating that Earth has had a solid crust for at least 4.4 billion years. Earth's mantle extends to a depth of 2,890 km, making it the thickest layer of Earth. The mantle is divided into upper and lower mantle. The upper and lower mantle are separated by the transition zone. The lowest part of the mantle next to the core-mantle boundary is
The Ego and Its Own is certainly true that we must first make a cause our own, egoistic cause, before we can do anything to further it. . . . [W]e are communists out of egoism also, and it is out of egoism that we wish to be human beings, not mere individuals... However, Marx and Engels would later collaborate on a lengthy criticism of Stirner's book in "The German Ideology" (1845, published 1932). The critique is a polemical tirade filled with ad hominem attacks and insults against Stirner (Marx calls him a "petty bourgeois individualist intellectual"). Stirner also had a lasting influence in the