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Louis Pasteur—What His Work Revealed

BY AWAKE! CORRESPONDENT IN FRANCE

CAN life appear by spontaneous generation? In the 19th century, some scientists thought so. They felt that life could originate by itself from nonliving matter, without intervention by a creator.

But on a spring evening in April 1864, an audience present at a meeting hall at the Sorbonne University in Paris heard something different. In a masterful presentation before a commission of scientists, Louis Pasteur successfully refuted, point by point, the theory of spontaneous generation.

This lecture and later discoveries made him “one of the world’s greatest scientists,” as The World Book Encyclopedia puts it. But why did this man make such an impression on those of his time, and how did he become known worldwide? In what way do we now benefit from some of his discoveries?

Early Research

Louis Pasteur was born in 1822 in the small town of Dôle, in the east of France. His father, a tanner, had ambitions for his son. In spite of having leanings toward art, as well as real artistic talent, Louis took up the sciences. He obtained a doctorate of sciences at the age of 25.

Early research of his had to do with tartaric acid, a compound present in the dregs left in wine barrels. The results of that research were used by other researchers a few years later to lay the basis for modern organic chemistry. Pasteur then moved on to the study of fermenting agents.

Prior to Pasteur’s research, the presence of fermenting agents such as yeast was known. But it was thought that they were the result of fermentation. However, Pasteur proved that these fermenting agents were, not the result of fermentation, but rather the cause of it. He showed that each type of fermenting agent caused a different sort of fermentation. The report that he published on this in 1857 is today viewed as “the birth certificate of microbiology.”

From that point on, his work and discoveries accelerated. Because of his reputation, the vinegar producers in Orléans called on him to solve their numerous technical problems. Pasteur proved that the agent responsible for the transformation of wine into vinegar was what is now called a microorganism, which was present on the surface of the liquid. At the end of his research, he presented before the town’s vinegar producers and dignitaries his famous “Lesson on Wine Vinegar.”

Pasteurization

Pasteur’s research into fermentation enabled him to conclude that the majority of problems of contamination in the food industry were caused by microbes. Microbes were present in the air or in improperly washed containers. Pasteur suggested that spoilage of food products by bacteria could be prevented by improving hygiene and that spoilage of a liquid could be prevented by maintaining a temperature of between 50 and 60 degrees Celsius for a few minutes. This method was first used on wine to prevent abnormal fermentation. The main microbes were killed without causing much change in the taste or bouquet.

This process, called pasteurization, which Pasteur patented, revolutionized the food industry. Nowadays this technique is no longer used for wine but is still adequate for numerous products like milk or fruit juice. However, other methods, such as sterilization at a much higher temperature, can also be used.

Another large industry to benefit from Pasteur’s research was the brewing industry. At the time, the French had many production problems and stiff German competition. Pasteur set to work and gave much advice to the brewers. He suggested that they pay attention to the purity of the brewer’s wort as well as to the general cleanliness of the surrounding air. The success was immediate, and he obtained many patents thereafter.

Life Comes From Life

From antiquity, the most fanciful ideas had been proposed to explain the appearance of insects, worms, or other creatures in decomposing matter. For instance, in the 17th century, a Belgian chemist boasted that he had made mice appear by stuffing a dirty blouse into a jar of wheat!

During Pasteur’s time the debate in the scientific community was heated. To confront the proponents of spontaneous generation was a real challenge. But as a result of what he had learned in his research on fermentation, Pasteur was confident. So he undertook experiments intended to put an end to the idea of spontaneous generation once and for all.

His experiment using swan-necked flasks is one of his most famous. A liquid nutrient left in the open air in an open-topped flask is quickly contaminated by germs. However, when stored in a flask that terminates in a shape like a swan’s neck, the same liquid nutrient remains uncontaminated. Why is this the case?

Pasteur’s explanation was simple: On passing through the swan-neck, the bacteria in the air are deposited on the surface of the glass, so that the air is sterile by the time it reaches the liquid. The germs that develop in an open flask are not produced spontaneously by the liquid nutrient but are transported in the air.

To show the importance of air as a transporter of microbes, Pasteur went to the Mer de Glace, a glacier in the French Alps. At an altitude of 6,000 feet, he opened his sealed flasks and exposed them to the air. Out of 20 flasks, only one became contaminated. He then went to the foot of the Jura Mountains and repeated the same experiment. Here, at the much lower altitude, eight flasks became contaminated. He thus proved that because of the purer air at higher altitudes, there was less risk of contamination.

Through such experiments Pasteur demonstrated convincingly that life comes only from previously existing life. It never comes into existence spontaneously, that is, by itself.

Fight Against Infectious Disease

Since fermentation requires the presence of microbes, Pasteur reasoned that the same had to be true of contagious diseases. His investigations into silkworm disease, a serious economic problem for silk producers in the south of France, proved him right. Within a few years, he discovered the causes of two diseases and proposed strict methods for selecting healthy silkworms. This would prevent epidemics.

While studying fowl cholera, Pasteur noticed that a culture of the germ that was only a few months old did not make the chickens ill but instead protected them from the illness. In effect, he discovered that he could immunize them with an attenuated, or weakened, form of the germ.

Pasteur was not the first to use vaccination. Englishman Edward Jenner had used it before him. But Pasteur was original in using the actual disease agent in an attenuated form rather than using a related microbe. He was also successful with a vaccination against anthrax, an infectious disease of warm-blooded animals, such as cattle and sheep.

Following this, he went on to wage his last and most famous battle, against rabies. Although he did not realize it, in confronting rabies, Pasteur was dealing with a world very different from that of bacteria. He was now dealing with viruses, a world that he could not see with a microscope.

On July 6, 1885, a mother took her nine-year-old boy to Pasteur’s laboratory. The child had just been bitten by a rabid dog. In spite of the mother’s pleading, Pasteur was reluctant to help the boy. He was not a doctor and risked being accused of the illegal practice of medicine. What is more, he had not yet tried his methods on a human. Nevertheless, he asked his collaborator, Dr. Grancher, to vaccinate the young boy. He did so, with good results. Out of the 350 people treated in less than a year, only one—brought too late—did not survive.

In the meantime, Pasteur was giving thought to hospital hygiene. Puerperal fever was causing the deaths of large numbers of women each year at the maternity hospital of Paris. Pasteur suggested aseptic techniques and strict hygiene, especially of the hands. Later investigations by the English surgeon Joseph Lister and others proved the accuracy of Pasteur’s conclusions.

Valuable Work

Pasteur died in 1895. But his work was valuable, and we benefit from aspects of it even today. That is why he has been called a “benefactor of humanity.” His name is still associated with the vaccines and procedures of which he is generally acknowledged to be the inventor.

L’Institut Pasteur, an institute founded in Paris during Pasteur’s lifetime for the treatment of rabies, is today a highly reputed center for the study of infectious diseases. It is particularly known for its work on vaccines and medicines—and even more so since 1983 when a team of its scientists, led by Professor Luc Montagnier, first isolated the AIDS virus.

The debate on the spontaneous generation of life, in which Pasteur was involved and in which he came off victorious, was not just a scientific quibble. It was more than an interesting point for a few scientists or intellectuals to discuss among themselves. It had much greater significance—it involved evidence that had to do with the existence of God.

François Dagognet, a French philosopher specializing in the sciences, observes that Pasteur’s “adversaries, both materialists and atheists, believed that they could prove that a unicellular organism could result from decomposing molecules. This allowed them to take God out of creation. However, as far as Pasteur was concerned, there was no possible passage from death to life.”

To this day all the evidence from experimentation, history, biology, archaeology, and anthropology continues to show what Pasteur demonstrated—that life can come only from preexisting life, not from inanimate matter. And the evidence also clearly shows that life reproduces “according to its kind,” as the Bible’s account in Genesis states. The offspring are always the same “kind,” or type, as the parents.—Genesis 1:11, 12, 20-25.

Thus, knowingly or not, through his work Louis Pasteur provided powerful evidence and testimony against the theory of evolution and for the absolute necessity of a creator for life to have appeared on earth. His work reflected what the humble psalmist acknowledged: “Know that Jehovah is God. It is he that has made us, and not we ourselves.”—Psalm 100:3.

[Pictures on page 25]

The apparatus above was used to pasteurize wine, killing unwanted microbes; it is highlighted in the drawing below

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Pasteur’s experiments disproved the theory of spontaneous generation

[Picture Credit Line on page 24]

All photos pages 24-6: © Institut Pasteur