Envy (from Latin invidia) is an emotion which occurs when a person lacks another's superior quality, achievement, or possession and either desires it or wishes that the other lacked it.
Aristotle defined envy as pain at the sight of another's good fortune, stirred by "those who have what we ought to have". Bertrand Russellsaid that envy was one of the most potent causes of unhappiness. Not only is the envious person rendered unhappy by their envy, Russell argued, but that person may also wish to inflict misfortune on others to reduce their status.
Psychologists have suggested that real or malicious envy should be distinguished from "benign envy"—malicious envy being proposed as an unpleasant emotion that causes the envious person to want to bring down the better-off even at their own cost, while benign envy involves recognition of other's being better-off, but causes the person to aspire to be as good. Benign envy is still a negative emotion in the sense that it feels negative.  However, Sherry Turkle considers that the advent of social media and selfie culture is creating an alienating sense of "self-envy" psyche in users, and posits this further affects problem areas attached to attachments. Envy and gloating have parallel structures as emotions.
According to researchers, benign envy can provide emulation, improvement motivation, positive thoughts about the other person, and admiration.This type of envy, if dealt with correctly, can positively affect a person's future by motivating them to be a better person and to succeed. Human instinct is to avoid negative aspects in life such as the negative emotion, envy. However, it is possible to turn this negative emotional state into a motivational tool that can help a person to become successful in the future.
One theory that helps explain envy and its effects on human behavior is the socioevolutionary theory. Based upon Charles Darwin's 1859 theory of evolution by natural selection, modern socioevolutionary theory predicts that humans behave in ways that enhance the reproduction of their genes. Consistent with envy being a motivation, it may boost attention and memory. Based on a model of evolved responses to those who are better off, Sznycer has argued that envy increases support for economic redistribution.
Often, envy involves a motive to "outdo or undo the rival's advantages". In part, this type of envy may be based on materialistic possessions rather than psychological states. Basically, people find themselves experiencing an overwhelming emotion due to someone else owning or possessing desirable items that they do not. For example, your next door neighbor just bought a brand new ocarina—a musical instrument you've been infatuated with for months now but can't afford.[tone] Feelings of envy in this situation would occur in the forms of emotional pain, a lack of self-worth, and a lowered self-esteem and well-being.
In Old Money, Nelson W. Aldrich Jr. states:
Envy is so integral and painful a part of what animates human behavior in market societies that many people have forgotten the full meaning of the word, simplifying it into one of the symptoms of desire. It is that (a symptom of desire), which is why it flourishes in market societies: democracies of desire, they might be called, with money for ballots, stuffing permitted. But envy is more or less than desire. It begins with the almost frantic sense of emptiness inside oneself, as if the pump of one's heart were sucking on air. One has to be blind to perceive the emptiness, of course, but that's what envy is, a selective blindness. Invidia, Latin for envy, translates as "nonsight", and Dante had the envious plodding along under cloaks of lead, their eyes sewn shut with leaden wire. What they are blind to is what they have, God-given and humanly nurtured, in themselves.
The things that drive people mad with envy change throughout their lifetime. Studies have shown that the younger the person, the more likely they are to be envious of others. Adults under the age of 30 are more likely to experience envy compared to those 30 years and older. However, what people become envious over differs across adulthood.
Younger adults, under the age of 30, have been found to envy others social status, relationships, and attractiveness. This starts to fade when a person hits their 30s. Typically, at this point in life, the person begins to accept who they are as an individual and compare themselves to others less often. However, they still envy others, just over different aspects in life, such as career or salary. Studies have shown a decrease in envy as a person ages; however, envious feelings over money was the only thing that consistently increased as a person got older. As a person ages, they begin to accept their social status. Nonetheless, envious feelings will be present throughout a person's life. It is up to the individual whether they will let these envious feelings motivate or destroy them.