Alien life is out there, but our theories are not helping us find it
If we discovered evidence of alien life, would we even realise it?
But is interpret the data we have with our current best theory, not with some upcoming idea. This is a significant issue for those involved in the search for extraterrestrial life.
Anticipate the unexpected.’
However, is it possible to’expect the unexpected’? These reflect a level of luck on behalf of the researchers involved. When it comes to alien life, is it enough for scientists to assume’we’ll know it when we see it’?
Results seem to tell us that expecting the unexpected is extraordinarily difficult. ‘We often miss what we do not expect to see,’ according to cognitive psychologist Daniel Simons, famous for his work on inattentional blindness. His experiments have shown how people can miss a gorilla banging on its chest. If our attention is occupied, in the former case, we overlook the gorilla. From the latter, we overlook the anomaly because we have prior expectations.
There are a lot of examples in the history of science. Philosophers describe this sort of phenomenon as’theory-ladenness of monitoring’. What we detect depends, quite heavily sometimes, on our notions, concepts, background beliefs and prior expectations. What we take to be important can be biased in this way.
By way of example, when scientists found evidence of low levels of ozone it was initially dismissed by them as data that was poor. It was ruled by the scientists out in advance, with no prior theoretical reason to expect a hole. Thankfully, they were minded to double check, and the discovery was made.
Could a similar thing happen in the search for extraterrestrial life? Scientists studying planets in other solar systems (exoplanets) are overwhelmed by the abundance of possible observation targets competing for their attention. In the last 10 years scientists have identified more than 3,650 planets – more than one a day. With missions such as NASA’s TESS exoplanet hunter this trend will continue.
Every exoplanet and each is full of physical and chemical complexity. It is so easy to imagine a case where scientists don’t double check a target that is flagged as’lacking significance’, but whose great significance will be recognised on closer analysis or using a non-standard theoretical approach.
We shouldn’t exaggerate the theory-ladenness of monitoring. From the Müller-Lyer illusion, a lineup in arrowheads pointing outwards appears shorter than an equally long line with arrowheads pointing inwards. Yet even if we know for sure that the two lines are the exact same length, our perception is unaffected and the illusion remains. Similarly, a sharp-eyed scientist might notice something her concept tells her she should not be seeing. And if just 1 scientist sees something significant scientist in the field will know about it.
History also demonstrates that scientists are able to notice surprising phenomena, even biased scientists who have a pet theory that does not match the phenomena. The 19th-century physicist David Brewster thought that light is made up of particles traveling in a straight line. But this didn’t influence his observations of numerous phenomena related to light, such as what is called birefringence in bodies. Sometimes observation is definitely not theory-laden, at least not.
We need to be open-minded
Certainly, scientists can’t proceed by just observing. Scientific observation needs to be directed. But at the same time, if we are to’expect the unexpected’, we can’t allow theory to influence what we see, and what counts as important. We need to remain open-minded, encouraging exploration of the happenings in similar scholars of yesteryear and the style of Brewster.
Studying the universe isn’t only a scientific endeavour – . The tendency to describe science disparagingly as’fishing expeditions’ is very likely to damage scientific progress. Areas need exploring, and we can not know in advance what we will find.
In the search for life, scientists have to be. And this means a certain amount of encouragement for techniques and non-mainstream ideas. Examples from previous science (including latest ones) show that non-mainstream ideas can sometimes be strongly held back. Space agencies such as NASA must learn from these cases if they believe that, in the search for alien life, we should’expect the unexpected’.