Nice syllogism
Old times were generally barbaric (were they all, like incas?) therefore retarded, woowoo beliefs are from the old times, therefore woowoo is retarded
Chicken have two feet, human have two feet, humans are chicken...
Sorry for this crash course on logic, on a scientific forum
About slavery, bloodletting and human sacrifice I'm sure Jimmy Saville's friends or Marc Dutroux's handlers would have something to say.
They might even have some interesting tidbits about this other tinfoil hattery known as "suppressed technology"!