Evolution of medicine :-
I have a headache ...
2000 BC - Eat
this root
1000 AD - That root is infected. 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. eat this root.