Because they are mutually exclusive theories.
Perhaps they are in most people's minds, but they don't have to be. A "creator" could have simply ignited the initial spark.
Explain the "Big Bang Theory", first posited by Roman Catholic Priest Georges Lemaître. Was Father Lemaître wrong? Was he evil?
Explain how scientists for 40 years discredited Lemaître's proposal as "Genesis masquerading as science"? Was this all part of some elaborate ruse?
“Why cant evolution and a creator coexist?” ~ ETL
“Because they are mutually exclusive theories.” ~ The Theophilus
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