Think of the sun and the moon, how they periodically repeat their movements. Think about when you wake up in the morning, you would first of all meet the dawn, that is when night (which is always dark) is gradually giving way to daytime (which is always light). Nighttime is always associated with some difficulties such as not seeing clearly the material things of nature, while daytime gives us light which enables us to see things very well. You know that this is what everyone of us experiences ever y time — nighttime giving way to daytime and daytime leading us into nighttime and vice versa. Do you know that these events are related to the daily ‘movement’ of the sun?
When the earth turns its face towards the sun, that region of the earth will have daylight, when it turns its back, the region will have nighttime. And you know that this is a continuous event which man has observed right from ancient times. This daily motion of the sun is simple to observe while the annual motions are far more difficult to observe. Both motions are also related to other important events that occur on earth such as the seasons.
In Nigeria, there are both the dry seasons and the rainy seasons while in European and American countries, they have winter, spring, summer, and autumn. These seasons as you know occur regularly, one changing into the other. Thus there are many regularities in nature which mankind has had to recognize for survival since human beings emerged as a species. These include births and deaths, storms and calms, the solid earth and the ever-restless seas, etc. The pattern and regularity of these changes can be expressed as rules or laws. These laws are called natural laws because they are derived from the natural properties of objects and phenomena.
Some people believe that some regularities are figments of human imagination. They say that the human mind leaps to conclusions because it cannot tolerate disorder or chaos. Thus it constructs regularities even when none objectively exists.These established by an impartial or true regularities must be unemotional examination of data.
Science must, therefore, employ a certain degree of doubt criticism to prevent premature generalisations. Science also insists on getting explanations of the causes of these regularities. It, however, does not permit some kinds of causes. For instance, attributing some causes to spiritual and divine forces is not permissible in science. Since scientists believe that the world is comprehensible, that is, understandable because there is order in the world, finding the causes of these regularities wouldn’t be problematic.
A theory explains how things are related or their common properties. In other words, when the properties and relationships between things are discovered, including their pattern and regularity of changes, they are then expressed as theories. A good theory, if you can remember from unit 3, has a predictive value. It prophesies certain results. But scientific prophecy does not say that something will certainly happen, but says only that something is likely to happen with a stated degree of probability. Thus theories that have proved to be so universally valid or true, that is, they are true anywhere in the world and have such a high degree of probability, are called natural laws. That means that not all theories are laws and laws also do not pronounce certainties. Based on this can you give an example of a natural law? The idea of a law-governed universe assumes that the universe unifisorm.
Examples of laws of nature are:
i Law of the uniformity of nature
ii Law of causation
iii The law of gravitation
iv The law of natural selection
There is a general belief that the universe and all aspects of it are law-governed and that the ordinary events or procedures of nature are uniform. This belief is found in primitive and traditional thought as well as in modern scientific thought. The birth of children, death, growth, normal and abnormal occurrences, lightning and thunder, the seasons, day and night, etc: these phenomena are usually explained in terms of general rules or causal laws. In traditional thought, these laws are believed to have a spiritual and teleological character.
This means that in traditional thought, when these events occur, for instance, death, the traditionalist believes that it was the gods who caused the death to occur and also that the death occurred for a purpose. Teleology is a view that developments occur because of the purpose or design they serve.
Therefore, traditional people look for the purpose for the occurrence of any event. If a tree, for instance, breaks or a house suddenly collapses, traditional mind will seek to explain such a happening in terms of the purpose, interest and wishes of some spiritual forces. Thus, the principles, laws or factors, which the traditional mind uses to explain the work of nature is often speculative, that is, meditational in character. Therefore the laws or factors may be superstitious and unreliable .
The scientist, however, explains the work of nature in terms of material, causal and rational factors. That means that the scientist reasons through and tries to find the causes by means of some activity. We cannot kn owledge of anything unless we are able to show why and how it occurs. This knowledge is expressed in terms of general rules or laws. Scientific laws are objective, factual and can be expressed in quantifiable (if you like mathematical) form. They are independent of our subjective wishes and interests.
