The original purpose of spices was to mask bad flavors, in contrast to their purpose today of providing good ones. For many centuries, black pepper -- considered the king of spices -- was prized for its ability to hide the taste of rotting food.THIS IS NOT TRUE.
I absolutely hate this idea. I have no idea where it came from, but it is all over in the culture, even in books published by National Geographic, co-authored by someone described as "one of the world's leading botanists."
First, rotting meat doesn't just taste bad, it is poisonous. Even if you hid the taste, assuming such a thing were possible, it would still make you sick.
Second, back in those olden days when this is supposed to have happened, black pepper was very expensive. No doubt there were people who sometimes ate dubious meat because it was all they could afford, risking illness to fill their bellies. They could not afford pepper. The people who could afford pepper did not have to worry about eating rotten meat.