The science in fiction: From gravity to microbiota

When talking about the science in science fiction, we often concentrate on technology or cultural developments that were correctly predicted in a novel. Of course, we all know that science fiction is not written to come up with correct predictions about the future, but comparing older novels with current developments is fun, nonetheless. At least as much fun is the opposite: where did novels get it completely wrong and why. One of the earliest examples is of course Jules Verne‘s De la terre à la lune (From the Earth to the Moon; 1865) in which three explorers are sent on a voyage to the moon aboard a “spaceship” that basically is a huge hollow bullet, fired from a gigantic cannon. Apart from the possibility (or, rather, impossibility) of such a launch mechanism, the novel contains a big mistake that nowadays even a kid in high school will immediately spot: the travelers are subjected to gravity all the way to the point where the gravitational fields of Earth and Moon cancel each other out and then experience a short period of weightlessness. After this their capsule turns around and they are henceforth subjected to the gravity of the moon. However, while the physics of the late 19th century certainly would have been able to predict accurately the weightlessness that the travelers would have experienced throughout the trip (apart from a brief moment at launch), it is easy to see how Verne could have made this mistake. Even much later, in the 1960s, even educated writers got much wrong about acceleration and the effects of its presence or absence. Hugh Walters (and not just him, either) had his astronauts lose consciousness at every launch because of the g-forces they were subjected to, for example.

Another mistake that probably only few people have noticed (mainly because the book is much less popular than Verne’s) is Robert A. Heinlein‘s Sixth Column (1941). It’s far from Heinlein’s best, but, then, even Heinlein’s weaker books are always worth a read. It was published almost a year before Pearl Harbor and portrays a future in which Japan and China are unified under a common emperor as “Pan Asia” and on a conquering spree. After annexing India, they take on the United States and after an apparently rather brief war occupy the country. The story follows a group of researchers hidden in a secret base in the Rocky Mountains who, just at the moment of surrender, discover a new powerful weapon. It is based on a kind of hitherto unknown radiation (not from the common electromagnetic spectrum, but from spectra resulting from different combinations of electrical, magnetic, and/or gravitational forces). These new types of radiations can have several effects, ranging from inducing severe fear to killing specifically some groups of organisms, while leaving others unharmed. Indeed, the researchers get on the trail of this weapon at the start of the novel when a mishap kills almost all people in the base, but not their laboratory mice and rats.

Later on as the story unfolds, one of the scientists realizes that the weapon can also be used for good, namely to cure infectious diseases. To put this to the test, he infects himself with anthrax and then heals himself by using the appropriate radiation to kill the anthrax bacteria. In fact, he also notices that a heavy head cold also disappears and realizes that by killing all microorganisms in his body, he has significantly improved his overall health. When I read this in the middle 70s or so, I already knew that this was incorrect: killing all his gut bacteria would at least have caused some digestive problems for this brave self-experimenting researcher… By now, of course, we know that such a treatment would have much more profound effects.

Recent research has revealed that the composition of our microbiota can influence almost anything you can think of. Having the right gut microorganisms may provide children with a more adaptive response to malnutrition (see also here). And your gut microflora may influence your susceptibility to psychiatric disorders such as depression. Of course, there is no way that Heinlein could have foreseen any of this, as microbiology was just in its infancy at that time: the first antibiotic, penicillin, had been discovered only a decade earlier and did not come into general use until more than a year after Sixth Column was published.

The discovery that our gut bacteria influence our brain and affect things like mood and such was probably a surprise for many people, even neuroscientists who have rightly described this finding as a paradigm shift. In retrospect, as with so many things, it’s much less surprising of course. We habitually try to influence our psychological state by using chemicals, be they recreational drugs or psychopharmaca like antidepressants. That different gut microorganisms, by producing different chemicals (or different quantities of the same chemicals) eventually entering our bloodstream, influence our psychological state is therefore perhaps unexpected, but not really too surprising. Perhaps also unsurprisingly, this has made the view that our behavior is molded by our genes in interaction with environmental influences even more simplistic than it already was. After epigenetics, now our microflora adds additional complexity. And just like genotype and environment complicate things by displaying complex interactions and covariations, it is to be expected that effects of our microbiota will depend on our genes and our environment (and any combination thereof), making things even more complicated. It really makes one wonder, given the current state of our knowledge, about the chances for success for the hugely expensive Human Brain Project.

Given the state of science in 1941, we should probably also credit Heinlein with some insights that were ahead of his time. In the same staff meeting where the above-mentioned scientist confesses to having infected himself with anthrax, the commander next directs the discussion to how best to use their discoveries for propaganda. The head scientist leaves the meeting disgustedly: he’s only interested in science, clearly implying that social science is not real science. In response, the commander reflects on why mass psychology, and psychology in general, would not be a valid field of scientific inquiry. One of the biologists knows the answer to that one: psychology is not a science, because it is too difficult. In a time when experimental psychology was still in its infancy, that’s quite a remarkable insight. In fact, given the above remarks about genes, microbiota, interactions, and what not, things are quite more complex than even Heinlein could have thought. Despite all the advances that we have made since the 1940s and the concomitant improvements in, for example, mental health, we are not at risk to be out of a job anytime soon, as we are still far from understanding how our brains work.

As I have said before: good science fiction makes you think