c. =Support and Protection of Weaker Members of Society.=--Young animals are supported and protected because they are unable to support and protect themselves. If they were not thus cared for the race would become extinct. Now, there are certain individuals, orphans for example, who have, through some accident, been deprived of their natural support and protection. If these weaker members of society, not yet able to support and protect themselves, were not provided for, they would perish and become thus lost to the race. From the time of primeval man to the present, these weaker individuals of society who have been deprived of their natural protectors, have been cared for by the stronger members of society and afforded such support and protection as they may need to make them independent. In a similar way the sick and defective members of society are cared for by the strong. Thus we see that the building and maintenance of orphanages, hospitals, asylums and "homes," are activities that belong clearly to the group of phyletic or altruistic activities. 2. SOME GENERAL PRINCIPLES OF BIOLOGY. Sacrifice and Compensation in Egoistic Activities. The thoughtful student is very likely to ask--Why does man till the fields? Why does man fell the forest trees? Why does he cultivate domestic animals? Why does he delve in the earth for minerals? These are all strenuous activities that require the outlay of time, talent and strength. We may say that they are sacrifices that he makes and, apparently, willingly. We have only to study the problem more closely to see that he tills the fields and cultivates his domestic animals for food; that he fells the forest trees to make for himself shelter; that he cultivates certain plants and animals to procure for himself clothing; that he delves in the earth to bring out mineral products to use in the various industries that supply various elements of his livelihood. It becomes manifest then that the egoistic activities of an organism represent sacrifice followed by compensation. The individual sacrifices in order that he may reap his reward or receive his compensation. It may be stated as a general biological truth that, _nature demands sacrifice or work on the part of all living organisms; and, under normal conditions, metes out a compensation commensurate with the sacrifice made_. Sacrifice and Compensation in the Phyletic Activities.