Mantle (geology) Mantle (geology) The mantle is a layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices, and are generally the largest and most massive layer of the planetary body. Mantles are characteristic of planetary bodies that have undergone differentiation by density. All terrestrial planets (including Earth), a number of asteroids, and some planetary moons have mantles. The Earth's mantle is a layer of silicate rock between the crust and the outer core. Its mass of 4.01 × 10 kg is 67% the mass of the Earth. It has
Civilization and Its Discontents Civilization and Its Discontents Civilization and Its Discontents is a book by Sigmund Freud, the founder of psychoanalysis. It was written in 1929 and first published in German in 1930 as "Das Unbehagen in der Kultur" ("The Uneasiness in Civilization"). Exploring what Freud sees as the important clash between the desire for individuality and the expectations of society, the book is considered one of Freud's most important and widely read works, and one of the most influential and studied books in the field of modern psychology. Freud enumerates what he sees as the fundamental tensions between civilization and the individual.