Why astrology is not scientific, while astronomy is?

This post is a continuation from:  Refuting a scientific theory: the theory of ether

As we have seen in the previous blogs, testability is the heart and soul of any scientific theory. However, as crucial as it might be, it is never sufficient to test a theory against the observations that led to its creation. A scientific theory must predict unknown facts that can only be confirmed by fresh observations.

As a simple example let's assume that after you had tasted sugar, you concluded that white, small-grained powders are sweet. The unscientific way would be to use sugar as a proof for your theory. The scientific way, on the other hand, would be to seek other white, small-grained powders and taste them. If you stayed alive after your experiment, you would have to admit that your theory was wrong. You will have to find another explanation for the sweetness of sugar.

If anything the theory predicts is proven wrong, the theory is incorrect. This potential refutability is a powerful criterion that distinguishes science from pseudoscience. Nowhere it is as clear as in the case of astronomy with astrology.

For thousands of years astrologers had been using the apparent movement of the sun, moon, and the five known extraterrestrial planets (Mercury, Venus, Mars, Jupiter and Saturn) to foretell earthly events. Once a sixth planet, Uranus, was discovered in 1781, astrologers added the new planet to their charts and continued with their foretelling as before, without asking whether astrology is still valid with the new planet, or why they had not foretold the existence of the new planet.

Astronomers, on the other hand, were fervidly forecasting the orbit of Uranus. Their calculations, however, based on Newton's theory of gravity, did not match the observed path of planet. There were two potential explanations: either the theory of gravity was wrong, or that the gravity of an unknown heavenly object, farther from Uranus, was responsible for the deviation. Using the same law of gravity, astronomers foretasted where the body that distorts Uranus' orbit should be. And they were right. In 1846, as predicted, they discovered a new planet, Neptune.

Just as discrepancies in the orbit of Uranus had led to the search for Neptune, irregularities in the orbit of Neptune, and to a lesser extent in the orbits of Uranus and Saturn, had led scientists to suspect the existence of a ninth planet. Once more, it was theoretical calculations that led to the discovery of Pluto in 1930. Their calculations were confirmed, and so was the theory of Gravity -- at least until the next observation.

To be continued ...

Refuting a scientific theory: the theory of ether

 
This post is a continuation from The Boundaries of Science

To demonstrate how established scientific theories can be refuted, let’s look at the theory of Ether, which was the dominant theory for an entire generation of scientists.

Since Maxwell (1831–1879) formulated the electromagnetic theory in 1865, 19th century scientists had puzzled how electromagnetic waves, such as radio or light, traveled through vacuum and the emptiness of space. Just like waves in water or sound in air, the argument went, electromagnetic waves needed a physical medium to travel through. For this reason alone, a new substance, ether, was proposed. (Although the term ‘ether’ was borrowed from Aristotle, the 19th century’s ether was a different concept altogether.)

According to the theory, ether filled in the entire universe, including vacuum and the inside of material bodies. As such, it had to be a weightless, transparent, frictionless matter that did not take part in any physical or chemical interaction, and was, therefore, impossible to test or verify.

Yet, the theory of ether could predict that light emanating from a moving object in the direction of its movement would travel faster than light emanating from the same object in any other direction. (To illustrate, imagine an item thrown from a moving car. Clearly, if we threw it in the direction of our travel it would travel faster than if we threw it in the opposite direction.)

Michelson and Morley relied on this hypothesis in 1887, when they attempted to determine the speed of earth in space by measuring the difference between the speed of a beam of light traveling in the direction of earth, and that of a beam of light traveling perpendicular to earth’s movement.

Had Michelson and Morley detected the difference they expected, it would have put their names, in a side note, as the first scientists to measure the absolute speed of earth. As it turned out, the experiment failed and no difference was detected. Even though Michelson and Morley could not explain their result, it was sufficient to inflict a death sentence on the theory of ether, and to win Michelson the 1907 Nobel Prize for physics. This experiment subsequently led Einstein to develop the theory of relativity.

The Boundaries of Science

This post is a continuation of The Origin of Evolution Theory

As strange as it may sound, modern science is not directly concerned with reality, but rather with models of it. Reality is the realm of philosophy. The essence of science is the scientific theory, whose purpose is to provide coherent explanations to observations; an objective aptly summed up by the physics Nobel laureate, Richard Feynman (1918–1988):

No one has ever seen the inside of a brick. Every time you break the brick, you only see the surface. That the brick has an inside is a simple theory which helps us understand things better. The theory of electrons is analogous … The electron is a theory that we use; it is so useful in understanding the way nature works that we can almost call it real.

Although theory is at the heart of science, not every theory is scientific. For a theory to be scientific it must first be internally consistent, that is, it should lead to no logical or mathematical paradoxes. If, for instance, a theory could lead to a conclusion that an object may simultaneously exist in two different places, the theory would not be consistent and cannot be deemed scientific. (This example is a paradox that contradicts the principle of space and time: a physical object exists separately in space and time in such a way that they are localizable and countable.)

Unlike mathematical models – which being the creation of the human mind require internal consistency only – scientific theories based on these models must be testable: that is, it does not matter how elegant or internally consistent a theory may be, if it does not agree with observations external to the theory, it is wrong. This requirement means that a theory can be considered scientific only after test criteria can be defined. That is, every theory is potentially refutable. Contrary to the common belief, turning an idea into a scientific theory does not necessarily improve it or make it more reliable. In many cases, it will lead, inadvertently, to the refutation of the idea.

Science vs. Religion -- the real question

In the outer rim of a 200 billion stars galaxy, a blue planet, earth, is traveling at a staggering speed of over 100,000 kilometers per hour. It would have disappeared in the vastness of space, if it were not for a mysterious and invisible force of gravity that keeps it orbiting, for all eternities, round a medium-size yellow sun, 150 million kilometers away. 

Every 176 years, four other planets: Jupiter, Saturn, Uranus and Neptune, are lined up on the same side of the sun. This was not known to the ancient astronomers and astrologers, whose picture of the universe did not include Uranus (discovered in 1781) and Neptune (discovered in 1846). This fact, however, inspired the farthest exploration in the history of humankind, when in 1977 two spacecrafts, Voyager 1 and Voyager 2, were launched to reach the aligned planets. The extraordinary photos they beamed back, and the new information they are still sending from the final frontier of our solar system, some 15 billion kilometers from home, have made this exploration a great triumph of science and our understanding of the laws of nature, without which none of this could have been achieved. 

These laws of nature: the principles of motion, action and reaction and gravity, are the very laws that started the age of scientific exploration and changed our understanding of nature forever. Although this new worldview did not directly contradict the principles of faith, it did threaten the monopoly the religious authorities enjoyed as the guardians of all knowledge, as declared, for instance, in the Council of Trent (1546): 

No one relying on his own judgment and distorting the Sacred Scriptures according to his own conception shall dare to interpret them contrary to that sense which Holy Mother Church, to whom it belongs to judge their true sense and meaning, has held or does hold, or even to interpret them contrary to the unanimous agreement of the Fathers. 

This powerful position was not to be given away without a fight; so rather than choosing to become the patrons of the sciences and embracing the new discoveries in order to strengthen faith and belief, the Church and its judicial institution, the Inquisition, chose to declare the new worldview heresy and its holders heretics. 

The birth of modern science into this environment still influences our way of thinking nowadays, nearly 500 years later. Because, while only esoteric minorities will not embrace the many improvements that only science could bring (medicine, transportation, communication, to name just a few) many still view the scientific worldview to be a threat to their beliefs. 

Is it a real threat? Must scientific and religious viewpoints collide, or can there be consistent description of the universe in which each is equally valid? These are deep philosophical questions that have been discussed for generations by religious people, scientists and philosophers. But whatever philosophical conclusions they may reach, for most of us, the real question is whether we, a society empowered by science-born technology, can afford to run our society on ancients principles devised far before the knowledge to create this technology was even conceived.