The correct word for the positive emotion is feeling emulous -- which means you are filled with admiration and the motivation to emulate the achievement you see, or to do even better. To feel envious involves a grudge and a desire to take away/undermine the achievement or possession of another person.
Example: do you wish you had a beautiful, new, fast car like your acquaintance; or do you wish they had an accident and lost their car (and/or got injured while in it)?
Helmut Schoeck wrote a great treatise on the subject of Envy. [1]
Example: do you wish you had a beautiful, new, fast car like your acquaintance; or do you wish they had an accident and lost their car (and/or got injured while in it)?
Helmut Schoeck wrote a great treatise on the subject of Envy. [1]
[1] https://www.amazon.com/dp/0865970645