2000 BC
Here, eat this root.

1000 BC
That root is heathen. Here, say this prayer.

1805 AD
That prayer is superstition. Here, drink this potion.

1940 AD
That potion is snake oil. Here, swallow this pill.

1985 AD
That pill is ineffective. Here, take this antibiotic.

2000 AD
That antibiotic doesn’t work anymore. Here, eat this root…

- Unknown