This is Hidden Brain, I'm Shankar Vedanta.

Way back in the 3rd century AD,

among in the Egyptian desert,

warned of evil spirits people should try to overcome.

In Christianity, these became known as the Seven Deadly Sents.

Pride, gluttony, greed, lust, sloth, wrath, and one more.

Envy.

It's an ugly, miserable, unflattering emotion, and it's universal.

Everyone at some time or another will experience this feeling of wanting what someone else has and resenting them for having it.

Hi, my name is Jessica Kyle from Atlanta, Georgia.

In 2014, Jessica and her best friend traveled to the remote Komoro Islands in the Indian Ocean.

They were there to teach English.

It was meant to be a grand adventure and could have been a high point in their friendship.

Except, Jessica and her friend got sick, really sick, with Denge fever.

I was single and she was married to a doctor and her husband was really worried about her and was able to get her evacuated to Kenya.

To Nairobi, to be exact, to a hospital with air conditioning, good food, and excellent medical care.

Jessica, meanwhile, was stuck on the island.

Where it was about 100 degrees and we had no electricity and I was very hot and didn't have any good food.

Jessica couldn't stop thinking about how her friend was getting much better care than she was.

Now, besides being sick, Jessica felt she was suffering from a new malaise.

I was really, really envious of her to the point where it was actually physically painful other than just having Denge fever.

That envy, I felt because I wanted to be in her place.

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