Sometime in the period of proto-history somebody invented the idea of the supernatural. He or they peopled the universe with a flock of capricious ghosts--gods, goddesses, spirits (both good and bad) of high and low degree, that controlled all the activities of nature. There was no conception of law and order; everything was the work of supernatural beings.
Western man later adopted Christianity, which reduced the number of gods to three and the number of goddesses to one and substituted a flock of disembodied saints for the spirits that formerly ruled the processes of nature. Christianity retained the great company of evil spirits and enthroned over them a master mind, whom it called the Devil. These supernatural beings were placed in charge of all the activities of nature and were constantly intervening in these activities. Christianity, like its predecessors, had no conception of law and order.
Both the Christian and pre-Christian conception of the cause of disease was based on the belief that disease is due to invasion of the body by evil spirits. Like its predecessor, Christianity also held that the supreme deity frequently inflicted disease upon men, women and children, even bringing about their death. There was no thought that man might bring disease upon himself by violations of the laws of nature, although it was thought that God might punish him for violations of the will of the priest-craft. The will of the priest was the will of God and anyone who defied the priest defied God.
Beginning about 2,500 years ago in Greece, there arose the idea that disease is due to natural causes and the medical profession, which came into existence at that time, largely abandoned the supernatural approach to the problems of health and disease. This supernatural approach was revived during the Middle Ages and was largely retained by the Protestant groups that developed out of the Reformation. Although the post-Renaissance medical profession largely repudiated the supernatural explanation of disease, the people themselves continued to hold to the ancient beliefs.
One of the first fallacies that the Hygienist had to overcome was the belief that life was subject to chance and haphazard or to the whims of a capricious Providence and was not governed or controlled like all else in nature, by immutable law. The churches had taught the people that their health and their sickness was subject to the capricious whims of God; the laws of life and health were not taught in the medical schools of the time as, indeed, they are not taught in the medical schools of the present. It was no easy task to bring the conception of law and order to the people and it was not uncommon to denounce Hygienists as "infidels" and "athiests" because of their insistence upon the reign of law in the realm of life.
The philosophy prevailed that the good who died young were fortunate; that is, they were blessed to escape from earth, with its trials and sorrows and enter upon another state of existence which, it was trusted, would be happier and better than life on earth. It was thought that God, who is wise and just and never does anything needlessly or without reason, somehow must have made some kind of mistake in sending souls to earth to live here for a "full lifetime," and found it necessary to recall the soul to heaven almost immediately after its birth on earth.
Hygienists rejected the view of some religious people that when little infants or people in the vigor and beauty of youth or in the strength and dignity of maturity die, they make a very desirable change in leaving a world of suffering, sorrow and toil for one of happiness and holiness. When they heard parents talk of having given back their little ones to God and, with every fiber of their being quivering with anguish, trying to gather comfort from the reflection that "what is our loss is their gain," "though we suffer, they are infinitely better off," they thought: how foolish is this philosophy that the best use that one can make of life is to dispose of it as soon as possible.
Hygienists declared that the principles of nature, the laws of science and the truths of the universe, are just as fixed and certain in their relation to the human organization, in relation to life, to health, to happiness, to disease and suffering, as they are in relation to all things else. To ascertain and understand the natural laws, or the regularity or uniformity with which everything occurs, and thus to found on a sure basis a system of mind-body care, was the aim of Hygienists. For, they declared that the very fact that a law exists in nature provides the necessity for obeying it. Indeed, they said, the existence of the law and obedience to it should be regarded as synonymous. It was their thought that those laws of being that are so intimately connected with our happiness and welfare should not be merely conjectural or of ambiguous significance. They are written out upon a scroll as broad as the face of nature and are exemplified in all that breathes.
Law (Latin: lex) has the same root as the verb signifying "to read." This arose out of the fact that of old, enactments to control the conduct of the community were read aloud in public. In this sense, law has reference to legislative enactments or imperial decrees; but when we use the term natural law, we signify the regularity with which forces and phenomena are produced and with which they behave. The inherence of laws is obvious. They are expressions of the qualities of things. Generally, the regularity of phenomena is so evident that it requires no proof to show it; but there are departments in which this regularity is not so easily discerned. In a general sense, a natural law may be defined as a mode of action and describes the regularity of nature.
We think that natural phenomena can be explained by natural laws, but we cannot separate the laws from the phenomena. What we call the law is the unvarying order of the phenomena. Order and regularity appear to be everywhere in the world of nature and this is all we mean by law. To recognize order and regularity does not explain them. The mere labeling and orderly arrangement of facts is not an explanation of them. The universal reign of a fixed order of things, which we call nature, enables us to reason from observed regularities into unseen causes. Law is a process, not a force, and operates everywhere so that we need to seek for the invariants that lie behind the changing surface of things.
When we formulate a law of nature, we simply state as succinctly as possible the orderly sequence of developments. To pass the test of validity, such a formulation of law must cut through superficialities and reveal underlying but hidden causal connectivities. It must explain fundamental relationships that recur so consistently that they cannot be fortuitous.
To repeat: natural laws are inherent in the nature of things and are essentially the same in all places and at all times. Every law of nature harmonizes with every other law of nature. All phenomena appear in conformity with fixed laws. All beings have a determinate nature. If this were not true, there could be no regularity of function. It became necessary for the Hygienists to make people realize that man is regulated by lawful processes unconsciously pursued and that his life is not the prey of outside beings.