Despite the claims of secular humanists, monotheistic religion was the basis of human scientific curiosity. Before monothesism, people believed in multiple gods, or in animal spirits, which controlled the world. In such an environment man did not attempt to make sense of the world around him, as he believed that all things were subject to the whims of whatever the gods or spirits decided to do. With monotheism, man became curious to find out how the one god had designed the universe. This lead eventually to scientific thought.
Wars and slaughter come out of human nature, they happen whether religion is involved or not.
Many enlightened secular types, like communists, believe that religion has out-lived its usefulness, and that it is holding mankind back. To me, saying that without religion mankind would find peace is like saying that by eliminating red and blue clothes, the Crips and the Bloods would stop fighting.
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