Love is a variety of different feelings, states, and attitudes that ranges from interpersonal affection to pleasure. It can refer to an emotion of a strong attraction and personal attachment. It can also be a virtue representing human kindness, compassion, and affection—"the unselfish loyal and benevolent concern for the good of another". It may also describe compassionate and affectionate actions towards other humans, one's self or animals. Non-Western traditions have also distinguished variants or symbioses of these states. This diversity of uses and meanings combined with the complexity of the feelings involved makes love unusually difficult to consistently define, compared to other emotional states. Love in its various forms acts as a major facilitator of interpersonal relationships and, owing to its central psychological importance, is one of the most common themes in the creative arts. Love may be understood as a function to keep human beings together against menaces and to facilitate the continuation of the species.