"Doctor, I have an ear ache."
2000 BC - "Here, eat this root."
1000 BC - "That root is heathen, say this prayer."
1850 AD - "That prayer is superstition, drink this potion."
1940 AD - "That potion is snake oil, swallow this pill."
1985 AD - "That pill is ineffective, take this antibiotic."
2000 AD - "That antibiotic is artificial. Here, eat this root!"
