"If I am virtuous and worthy, for whom should I not maintain a proper concern?" (Confucius).
WE'RE NOT FULLY HUMAN IF WE DON'T RECOGNIZE OUR CONNECTION TO OTHER HUMAN BEINGS. There is a sense in which the human race can be thought of as a family, and family members have important reasons to treat one another unselfishly and with benevolence. For one thing, family members are attached to one another in such a way that whatever one does affects all the others. In the human family, we need to recognize that each of our own actions has some impact on our siblings. If nothing else, we have to share the same living space, the same habitat. To misuse the world which is our home or to take too much out of it, just for our own indulgence, is to be shamefully selfish. To fail to help the helpless is to withhold good things from the family of which we ourselves are a part. Connected as we are, how can we not be concerned about one another?
"Altruism" means selflessness. It's an active concern for the welfare of others. When we choose to be altruistic, we're making a choice to be humane and helpful. "A man of humanity is one who, in seeking to establish himself, finds a foothold for others and who, desiring attainment for himself, helps others to attain" (Confucius).
There is a danger, however, in saying that we "love humanity." That kind of sentiment can be so vague and general that, for all practical purposes, it's useless. Dostoevsky said, "In abstract love of humanity one almost always only loves oneself." We'd do better to love actual persons -- real ones, like those who live in the house next door or work in the office down the hall -- rather than "humanity."
If we're not as altruistic as we should be, we need to start growing in that virtue. Yet there's no denying that it's hard. It demands a great deal of us. Just because we don't think we're doing any harm to anybody, that doesn't mean we're doing the good that we should do. In the words of Roy Masters, "Loving what is right is different from hating what is wrong and feeling right about it." And frankly, the more affluent we are, the more we need to be warned: altruism isn't a philosophy -- it's a lifestyle that results in the positive blessing of other people.
"To hoard is worse than to steal" (Jewish Proverb).