Sympathy comes from the Latin sympatha, from Greek sumpatheia, from sumpaths, affected by like feelings : sun-, syn- + pathos, emotion. Thus the essence of sympathy is that a person's feelings reflect or are like those of another.
Sympathy exists when the feelings or emotions of one person give rise to similar feelings in another person, creating a state of shared feeling. In common usage, sympathy is usually the sharing of unhappiness or suffering, but it can also refer to sharing other (positive) emotions as well. In a broader sense, it can refer to the sharing of political or ideological sentiments, such as in the phrase "a communist sympathiser".
COMPARE WITH EMPATHY
The psychological state of sympathy is closely linked with that of empathy, but is not identical to it. Empathy refers to the ability to perceive and directly experientially feel another person's emotions as they feel them, but makes no statement as to how they are viewed. Sympathy, by contrast, implies a degree of equal feeling, that is, the sympathiser views the matter similarly to how the person themselves does. It thus implies concern, or care or a wish to alleviate negative feelings others are experiencing.
Thus it is possible to be:
- Empathetic but not sympathetic, by internally experiencing their feeling but not being motivated to alleviating action as a result (eg, a lust killer who is aroused by his victim's fear, or a con artist who knows how his "mark" feels but uses it to manipulate not support).
- Sympathetic but not empathetic by realising (perhaps cognitively) someone is upset and wanting to alleviate that, but not experiencing their sense of upset directly and internally as an emotional state within themselves (eg, a person at a help desk who sees another in distress, does not feel distress themselves, but tries to find what is wrong and help them anyway).