Monday, March 30, 2015

Science Is Often Speculative

Human Thought

I am a firm believer, that without speculation there is no good and original observation.
Charles Darwin
Letter to A. R. Wallace (22 Dec 1857).
In Alfred Russel Wallace and Sir James Marchant (ed.),  
Alfred Russel Wallace: Letters and Reminiscences (1916), 109

[Science] is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. ... The obvious is sometimes false; the unexpected is sometimes true.
Carl Sagan
Cosmos (1985): 277

Carl Sagan [1934-1996] at the Very Large Array in New Mexico. Sagan said in a 1996 interview for NOVA that the existence for extraterrestrial life must go beyond speculation to rigorous proof:
“I personally have been captured by the notion of extraterrestrial life, and especially extraterrestrial intelligence, from childhood. It swept me up, and I've been involved in sending space craft to nearby planets to look for life and in the radio search for extraterrestrial intelligence.    It would be an absolutely transforming event in human history. But, the stakes are so high on whether it's true or false that we must demand the more rigorous standards of evidence—precisely because it's so exciting. That's the circumstance in which our hopes may dominate our skeptical scrutiny of the data. So, we have to be very careful. There have been a few instances in the [past]. We thought we found something, and it always turned out to be explicable.”
Photo Credit: Cosmos/Discovery

The title is correct; science often makes speculative theories of what it yet does not know or fully understand. Speculation is the means of bringing forth new ideas to advance our thinking; speculation is the fount of progress; speculation is the oxygen of human advancement and achievement.

But this is only the beginning of the hard work that can take decades (or longer) for an idea or developed theory to gain acceptance. This “speculation” is one way to bring about the testing of a hypothesis and the debating and discussing of experimental results. It is also a way to advance an idea, inchoate as it might be, to make it more understandable at first in the community of scientists and then, if found valid and true, to the general community. Speculative theories have to be tested in accordance to the standards of science and its scientific method. Speculation alone is insufficient; it must be tested and done so rigorously and without bias.

Speculation is not bad; it is actually good and necessary.  This is how human progress. Speculate. Test. Reason. Debate. Retest. Confirmation. Good and original ideas are the best, but these are always in short supply, and these are always the ones that receive the most arguments against it. This is not to suggest that all original ideas are good. Most are likely not. But it is probably true that in the annals of science, all ideas that are now viewed as great and wonderful were original, and at first viewed with suspicion and scorn by the scientific community. That is, they were not accepted easily in their time.

Galileo Galilei, the 17th century Italian physicist and astronomer, is considered The Father of Modern Science. As Galileo points out: “All truths are easy to understand once they are discovered; the point is to discover them.”

There are many notable examples, including 1) when Nicolaus Copernicus of Poland, in 1514, published Commentariolus (Latin for “Small Commentary”), in which he described the heliocentric planetary system, it was not immediately accepted by scientists and, moreover, its findings incensed Church authorities; 2) when Galileo Galileo of Italy, in 1632, in support of the Copernican theory, published the Dialogue Concerning the Two Chief World Systems, he was convicted by the Catholic Church of heresy and spent the remaining years of his life under house arrest. Galileo is considered as the Father of Modern Science, a title that many scientists today say is well-deserved; 3) when Ignaz Semmelweis of Hungary, in 1847, came up with the model of infection control, chiefly through hand washing, physicians mocked him and his ideas; his book, Etiology, Concept and Prophylaxis of Childbed Fever, published in 1861, was mocked and viewed as irrelevant by many leading scientists at the time, notably by  Rudolf Virchow, considered the leading authority, a few years later, Semmelweis died in ignominy.

Some speculative ideas receive little objection. When Charles Darwin of England, in 1859, with On the Origin of the Species, his ideas were not vociferously attacked, as one would expect, except primarily by those of the religious community, which is the situation today. By 1870, natural selection and evolution were considered true and valid by most of the scientific community and of the general public.And, of course, Albert Einstein of Germany, who, in 1905, published his paper on the special theory of relativity, it became a serious topic of discussion at first within Germany, and then elsewhere. By 1919, it was widely accepted by the scientific community, only 14 years after the initial paper.

For an interesting article on why Einstein's theory was easily adopted, see “Why was Relativity Accepted” in Physics in Perspective  1 (1999) 184 – 21 by Stephen G. Brush. One of the convincing arguments is that it takes someone in a position of authority to first accept the theory and act as its advocate, thus convincing and, perhaps, compelling other scientists to seriously consider its validity. In Einsteins' case, Max Planck and Arthur Eddington were early supporters of the theory.

Brush writes:
Why was relativity accepted? The historical studies reviewed in this paper can be put together to suggest a three-stage answer. In the first stage, a few leading scientists such as Planck and Eddington adopted the theory because it promised to satisfy their desire for a coherent, mathematically sophisticated, fundamental picture of the universe. In the second stage, their enthusiastic advocacy persuaded other scientists to work on the theory and apply it to problems that were currently of great interest: the behavior of electrons, and Bohr’s atomic model. The special theory was accepted by many German physicists by 1910 and had begun to attract some interest in other countries.

In the third stage, the confirmation of Einstein’s light-bending prediction attracted so much attention among the general public as well as among scientists that no one could ignore it after 1919. Physicists who had not previously accepted relativity now had to take it seriously, and when they did, they were persuaded of its validity bya combination of factors.
This might apply to all ground-breaking theories. Such are only a handful of examples of scientists’ speculation that changes the way we think and view the world. Such is the way it is with us humans. We do not easily accept change, even if the ideas are proven true, but will open our minds to the possibility if within the theory there is something that is already agreeable. Science on the whole is skeptical and cautious, which are good qualities.

Then there are the far-out theories, such as the idea of extraterrestrial life. Sagan says in chapter 17 (“The Marriage of Skepticism and Wonder”) of The Demon-Haunted World : Science as a Candle in the Dark (1995) about the human and scientific need to balance openness and wonder with skepticism and caution:
 At the heart of science is an essential balance between two seemingly contradictory attitudes - an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. The collective enterprise of creative thinking and skeptical thinking, working together, keeps the field on track. Those two seemingly contradictory attitudes are, though, in some tension.
It is this through the working out of this tension that great discoveries are made.