HUMAN BEING. Humankind is a species with a scientific name (Homo sapiens), but it lacks a convenient common name, such as rabbit, mouse, or hamster. “Man” increasingly meets objections from those who believe it covers only half of humankind. Human beings do constitute a single living species (biologists regard the several human races as subspecies), whereas the term “rabbits” denotes 15 living species; “hamster,” 11 species; and “mouse,” hundreds of species.

人类。人类是一个拥有科学名称（智人）的物种，但它缺乏一个如兔子、老鼠或仓鼠那样方便通用的名称。“人”这个名称不断遭遇到来自认为它只涵盖了人类一半含义的那些人的反对。人类确实构成了一个单一的现存物种（生物学家认为一些人类种族是亚种），而“兔子”这个术语是指15种现在的物种；“仓鼠”为11种；而“老鼠”则有数百种。

1. What Is a Human Beings?

   To explain what a human being is one begins with biological classification. Humans belong to the animal kingdom. They consist not of one cell only but of many cells, so they are metazoans rather than protists. Since they have spinal columns, they are vertebrates rather than invertebrates. Of the major groups of vertebrates—fishes, amphibians, reptiles, birds, and mammals—humans are mammals, because they are warm-blooded, air-breathing animals with a covering skin that bears hair. One could readily identify human as mammals simply by noting their breasts. A characteristic feature of this class, the feature that gives it its name, is its method of reproducing and nourishing the young. The young of most mammals develop within the body of the mother. They are born relatively helpless and nourished for a while by sucking at the mother’s breasts (mammae).

1、人类是什么？

    要解释人类是什么，那得从生物学分类开始。人类属于动物王国。他们不仅由单细胞组成，也是由多细胞组成，因此他们是多细胞动物，而非单细胞动物。由于他们拥有脊柱，因此他们是脊椎动物，而不是无脊椎动物。其中，脊椎动物的主要群类有---鱼类、两栖类、爬行类、鸟类和哺乳类动物---人类是哺乳类动物，因为他们是温血的，呼吸空气的动物，拥有长有毛发覆盖着的皮肤。人们通过简单注意一下她们的胸部就能很容易地识别人类是哺乳动物。本课的一个特征，就是赋予其名称的特征，是其繁殖和养育幼崽的方式。大多数哺乳动物的幼崽是在其母体内发育的。它们出生后相对无助，是通过吮吸母亲的乳房（乳汁）生存一段时间。

   Mammals are divided into THREE groups, according to their method of reproduction. Prototheria, a transition between reptiles or birds and mammals, lay eggs, hatch them out and then suckle the young at the breast. The duckbill is an example. The other two groups, Metatheria and Eutheria, nourish their embryos in a maternal uterus by means of a placenta. One side of this disk-like organ is embedded in the wall of the uterus; the other side gives origin to the umbilical cord, through which nourishment is carried to the embryo. After the young are delivered, the placenta becomes detached and is expelled. Metatheria are pouched mammals, or marsupials, such as the kangaroo and opossum. They have poorly developed placentas. Eutheria are mammals in which the placenta is well developed. Humans belong to this group.

    根据哺乳动物繁殖的方式，它们被分为三类。原哺乳亚纲，在爬行动物或鸟类和哺乳类之间的一种过渡类，卵生，孵化出生，然后幼崽吮吸乳房。鸭嘴兽就是一个例证。其它两类，后兽次亚纲和真兽亚纲，在母系的子宫内通过胎盘滋养胚胎。这种盘状器官的一边嵌入子宫壁内；另一边与脐带原点连接，通过它将营养带到胎盘。幼崽出生后，胎盘脱落并排出体外。后兽次亚纲是有袋哺乳动物，或有袋动物，比如袋鼠和负鼠。它们有发育不全的胎盘。真兽亚纲是胎盘发育良好的哺乳动物，人类就属于这类。

   Human beings also are primates, members of the mammalian order Primates, which includes lemurs, tarsiers, monkeys, and anthropoid apes—orangutans, gorillas, and chimpanzees. A number of characteristics distinguish the human being from other living primates and from the extinct primates that were their evolutionary ancestors. Humans walk on two feet (bipedalism). Their normal posture is upright, and the vertebral column has an S-curve. The legs are longer than the arms. Only the hands are prehensile, with a large strong thumb that by touching (opposing) the fingers permits grasping. Most of the body is bare or has only short, sparse hair. The jaws are short with a rounded dental arch. The short and nearly vertical face is positioned under the front of the brain, which is uniquely large in proportion to the body and has a large and complex cerebral cortex.

    人类还是灵长类动物，哺乳动物类的灵长类成员，这包括狐猴、眼镜猴、猴子和类人猿（“像人的”）---猩猩、大猩猩和黑猩猩。许多特征将人类与其它现存的灵长类以及曾是它们进化祖先的，已经灭绝的灵长类动物区别开来。人类用双足行走（直立行走）。他们的正常姿势是直立的，而且脊柱有一种S型曲线。腿比手臂更长。只有双手适于抓握，拥有一个强大的大拇指，通过接触（相对的）手指来抓紧东西。身体的大部分是光秃秃的，或只有短而稀疏的毛发。下巴短，拥有圆形的齿弓。短而几乎垂直的脸位于头部的前下方，头部占身体的比例特别大，并且拥有大而复杂的大脑皮层。

   Humans also have distinctive traits that are related more to psychology than to anatomy. For example, human behavior is more flexible and less instinctive than that of other animals, in proportion to the higher human intelligence. Humans share curiosity, imitation, attention, memory, and imagination with other advanced animals but have them in higher degree and apply them in more intricate ways. Humans reason and improve the adaptive nature of their behavior in rational ways. They make and use tools in great variety. They are self-conscious, reflecting on their past and future, on life and death. They make mental abstractions and develop symbols, of which language is the most essential and complexly developed. Humans (at least some of them) have a sense of beauty. They have a religious sense, taking that term broadly to include awe, superstition, and belief in the animistic, supernatural, or spiritual. The human being is a moral animal and has developed complex cultures and societies. One unique cultural feature is the wearing of clothes.

人类还具有更多的与心理学而不是解剖学相关的，与众不同的特征。例如，人类的行为更灵活，比其它动物更少了本能，这与更高的人类智能相对称。人类会分享求知欲、模仿、注意力、记忆力，并模仿其它高级动物，并使它们达到更高的程度，并以更复杂的方式应用它们。人类以理性的方式推断并改善他们行为的适应性。他们制造并使用各种工具。他们自觉地反思过去，思考未来，思考生与死。他们进行精神抽象并创造符号，语言是其中最基本、最复杂的创造。人类（至少它们中的一些）拥有美感。他们有宗教意识，从广义上理解这个术语它包括敬畏、迷信，以及对万物有灵、超自然，或精神的信仰。人类是一种有道德观的动物，并发展出复杂的文化和社会。穿着衣服是一种独特的文化特征。

                                         WILLIAM S. BECK, M. D., Harvard University

                                         威廉·S. 贝克，哈佛大学医学博士

                                                2022年10月17日译

（译者注：该词条位列《大美百科全书》1985年版，第14卷，第545页）