The History of Medicine
2000 B.C. - Here, eat this root 1000 A.D. - That root is heathen. Here, say this prayer. 1850 A.D. - That prayer is superstition. Here, drink this potion. 1940 A.D. - That potion is snake oil. Here, swallow this pill. 1985 A.D. - That pill is ineffective. Here, take this antibiotic. 2000 A.D. - That antibiotic doesn't work anymore. Here, eat this root. Received from Laugh-A-Lot.