Structure of Science
Stephen Hawking occupied the Lucasian Chair at Cambridge previously held by Sir Issac Netwon and devoted his life to the study of cosmology. As the origin and ultimate fate of the universe impinges on religious questions, it is perhaps inevitable that he was thrust into the metaphysical implications of his studies. It has been suggested that Hawking believed there is no need to invoke the concept of God to answer the question of how the universe came to be. This can only be a misreading because it is a logical impossibility for science to have an opinion on the matter.
This is because science is ultimately a description only of phenomena we can experience through our senses. As a result science is antithetical to superstition and religions that deny the Judeo-Christian concept of “secondary causation.” But this does not imply that science and religion are in conflict. Rather they both inform the other to form a coherent whole of human knowledge. It was this thinking that motivated the Catholic to invent modern science beginning in the early middle ages.
Indeed, the Book of Genesis in the Bible for the first time in human history provides a polemic against magic and mysticism. Rather than nature being animated by numerous mischievous spirits or a pantheon of gods and goddesses, or an all-powerful tribal-chief god who recreates everything micro-second by micro-second according to his arbitrary whim, or by unexplainable and unquantifiable cosmic forces that somehow oscillate between opposites to achieve a mystical balance, Genesis postulates a universe created with its own intrinsic properties which, once created, evolves according to consistent and understandable natural laws. Looking beyond the undeniable beauty of the allegorical description of creation in the Bible, which mainstream Christianity has always taken to be inspired but not dictated, to the enshrined moral principles, the tradition of Genesis over the last four millennia, is the foundation on which the invention of modern science by the Catholic Church is based.
But as our understanding of science advances, we ever more recognize its limits. Science rather than being the answer to everything continues this logical retreat into smaller and smaller gaps of expertise which began with its inception in the ancient world of Classical Greece.
The most fundamental assumptions of science are as follows.
1. The cosmos is composed of numerous physical objects which have an independent existence apart from ourselves.
2. All physical objects have intrinsic properties which are uniform and consistent.
3. Everything is constantly being rearranged in accordance with relatively simple and orderly natural laws.
4. The human mind through observation and reason can discover these laws.
If you look up in the sky and see a full moon, but then look away for a second, we normally assume it is still there shining down on us. If a tree falls in the forest, science assumes it makes the same amount of noise whether anyone is around to hear it or not. This is generally called “counterfactual definiteness”. This common sense belief may seem trivial but has profound implications in many aspects of science. In particular, a strict reading of the equations of quantum mechanics seems to want to violate this principle. Einstein and many others regarded this interpretation as so contrary to experience and logic as to be nonsense.
Assuming that the basic assumptions are correct, there are several consequences that logically follow.
1. Any time anything changes, it must have had a physical cause.
2. A cause always comes before any physical effect.
3. The natural world is predictable and not subject to the control of ever changing, mystical, and arbitrary forces.
4. Everything in the natural world must either have existed forever or have been created from nothing in a supernatural event.
SCIENCE IN PRACTICE
In practice we follow the
1. Measure some physical effect and accumulate the data.
2. Make a guess as to what underlying natural law might cause such behavior.
3. Calculate the consequences of this new law and compare it against the original data.
4. Try to predict something not yet observed and see if theory matches new experiments.
5. Select between alternate theories and choose the simplest explanation.
In general, science is conducted not by philosophers but by very fallible human beings. And so the normal progression is as follows:
1. Measure some physical effect and accumulate data.
2. Try to fit a curve to this data using likely mathematical functions and by adjusting a variety of arbitrary parameters.
3. If one gets a match, try to simplify the equations.
4. Propose a simple physical reason why the equation works by assuming a new law of nature.
LIMITS OF SCIENCE
As our scientific expertise improves,
1. Because all scientific calculations are based on assumptions to include mathematical axioms, we can never be certain the natural laws we assume to exist actually do.
2. Because we cannot observe everything that happens nor to infinite precision, we can never be certain any new law is the correct formulation.
These are not limits because we haven’t yet solved some mystery or discovered some new law. Rather these limits are the logical consequence of us knowing too much science rather than too little. And as such they constitute a profound scientific discovery in their own right.