Love is a variety of different emotional and mental states, typically strongly and positively experienced, that ranges from deepest interpersonal affection to simple pleasure. An example of this range of meanings is that the love of a mother differs from the love of a spouse differs from the love of food. Most commonly, love refers to an emotion of a strong attraction and personal attachment. Love 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.Ancient Greek philosophers identified four forms of love: essentially, familial love (in Greek, storge), friendly love, romantic love, and divine love. Modern authors have distinguished further varieties of love: infatuated love, self-love, and courtly love. Non-Western traditions have also distinguished variants or symbioses of these states. Love has additional religious or spiritual meaning. 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.