Love is a variety of different feelings, states, and attitudes that ranges from interpersonal affection ("I love my mother") to pleasure ("I loved that meal"). It can refer to an emotion of a strong attraction and personal attachment.[1] It can also be a virtue representing human kindness, compassion, and affection—"the unselfish loyal and benevolent concern for the good of another".[2] It may also describe compassionate and affectionate actions towards other humans, one's self or animals.[3] Ancient Greeks identified four forms of love: kinship or familiarity (in Greek, storge), friendship (philia), sexual and/or romantic desire (eros), and self-emptying or divine love (agape).[4][5] Modern authors have distinguished further varieties of romantic love.[6] Non-Western traditions have also distinguished variants or symbioses of these states.[7] 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.