"Doctor,Ihaveanearache."
2000B.C.-"Here,eatthisroot."
1000B.C.-"Thatrootisheathen,saythisprayer."
1850A.D.-"Thatprayerissuperstition,drinkthispotion."
1940A.D.-"Thatpotionissnakeoil,swallowthispill."
1985A.D.-"Thatpillisineffective,takethisantibiotic."
2000A.D.-"Thatantibioticisartificial.Here,eatthisroot!"