The Dr. King uses an allusion when he refers to the Reverend Reinhold Niebuhr, who is an American theologian and professor and also a leading intellectual during the mid-20th century. The reverend Niebuhr wrote several influential books and there was one that addressed the morality of the individual versus the immorality of the society. He is also credited with writing the Serenity Prayer. Dr. King writes "History is the long and tragic story of the fact that privileged groups seldom give up their privileges voluntarily."
all countries tried their best to reconstruct the gold standard system in hoping to stabilize the price, to restore the frozen trade, and to push the economic recovery.
The Maya Empire, centered in the tropical lowlands of what is now Guatemala, reached the peak of its power and influence around the sixth century A.D.
The Maya excelled at agriculture,
pottery, hieroglyph writing, calendar-making and mathematics, and left behind an astonishing amount of impressive architecture and symbolic artwork.
Most of the great stone cities of the Maya were abandoned by A.D. 900, however, and since the 19th century scholars have debated what might have caused this dramatic decline.
The Classic Maya built many of their temples and palaces in a stepped pyramid shape, decorating them with elaborate reliefs and inscriptions. These structures have earned the Maya their reputation as the great artists of Mesoamerica.
Guided by their religious ritual, the Maya also made significant advances in mathematics and astronomy, including the use of the zero and the development of complex calendar systems like the Calendar Round, based on 365 days, and later, the Long Count Calendar, designed to last over 5,000 years.
Serious exploration of Classic Maya sites began in the 1830s. By the early to mid-20th century, a small portion of their system of hieroglyph writing had been deciphered, and more about their history and culture became known.
Most of what historians know about the Maya comes from what remains of their architecture and art, including stone carvings and inscriptions on their buildings and monuments.
The Maya also made paper from tree bark and wrote in books made from this paper, known as codices; four of these codices are known to have survived.
They are also credited with some
of the earliest uses of chocolate and of rubber.
