Science seeks to get the same result when an experiment or observation is repeated, regardless of who is doing the experiment and what their beliefs are. This is what is meant by science being objective, it is a fundamental principle of the basic scientific process proposed by Francis Bacon. However, the ability for science to be truly objective has been questioned over the centuries.
The basic scientific process, of drawing rational conclusions from observations in an objective way, comes under the category of ‘naive inductivism’. Why is it called naive? In reality doing science is more complicated than being purely rational. Scientists are people and, no matter how hard we try, we will bring our beliefs, assumptions and unconscious biases into our work. Scientists live and work within a society and culture that also brings it’s own set of beliefs and prejudices and this will have an impact on the work too. The view that science can be subjective as well as objective is called ‘sophisticated inductivism’ - we reach conclusions in a more sophisticated way than by using pure logic and, in this context, sophisticated means subjective or non-rational.
So how can being subjective and non-rational still be considered as being scientific? It can if it is applied to the discovery of new ideas. Consider how someone comes up with a new idea or a new type of experiment; it is a creative process. How people come up with creative ideas is not really understood but we know that it need not be rational; it can come from a dream, a belief, from religion, from thinking random thoughts, from watching TV or talking to someone about something totally unconnected. Creativity is a subjective process; and yet it is an important part of doing science. How can we reconcile these two processes, the rational justified knowledge and the non-rational creative ideas for new discoveries?
In the first half of the 20th century there were three main approaches to this reconciliation.
In the 1960s, a new scientific reasoning was introduced into the debate and revolutionised the way we view the scientific process. Thomas Kuhn (1922 1996) was a philosopher and also a physicist and historian. Rather than rely on existing versions of how scientific ideas were changed, Kuhn studied the key scientific revolutions from the perspective of an historian. He started with the Copernican revolution and realised that the acceptance of the heliocentric universe was not simply about scientific evidence and reasoning winning the argument over religious dogma. What actually happened was far more complicated. He studied other revolutions in science and wrote his findings in “The Structure of Scientific Revolutions". This has been an influential book in the management of science and the way we think about scientific methodology today. It brought about an acceptance that science is, and can be, done in a non-rational way and still be science.
Kuhn argued that each scientific discipline has it’s own set of preferred skills, methods and theories that provides the framework of that discipline. He called this the ‘paradigm’ that scientists work in. It includes the successful parts of the science that an individual learns that provides them with the basis for all their future scientific work, for example, all the standard problems and solutions that are practised at school. The word ‘paradigm’ is now widely used due to Kuhn, and can be considered as ‘the way we look at the World or a situation’.
Kuhn divided the scientific process into two activities:
Kuhn’s study of scientific revolutions turned up some unexpected results that challenged the accepted views at the time. Previously it was assumed that science was a cumulative growth of knowledge, a view encapsulated in the famous quote by Newton “If I have seen further than others it is by standing upon the shoulders of giants”. Kuhn said this is not how revolutions happen. They are not achieved in a gradual way but are a comprehensive change of the view of the World - a ‘paradigm shift’ - and result in a new way of practising science and a new set of problems to investigate. Revolutions require an abandonment of past theories but, importantly, the abandoned theories do not become unscientific since they were also developed from similar scientific reasoning and methods that we use today.
Kuhn also said that revolutions only happen when a viable alternative view is available as well as scientists to support the new view who can persuade other scientists of it’s validity. He said “Most scientists most of the time are committed to their paradigm and work to prove it even in the face of refuting evidence”.
Figure 2.2: Revolutions in science. When science is in crisis the number of theories goes up and the number of scientists supporting the paradigm goes down. A change in theory does not happen quickly but takes time for scientists to accept the new paradigm. Credit: C. Devereux and P. Farrell.
Kuhn's exploration of revolutions in science showed that evidence alone is not enough to get a paradigm shift. When one serious anomaly occurs then it is often not questioned by the scientific community. When more occur then some scientists begin to question the core assumptions that the paradigm is based on, for example, is the universe expanding? Alternatives are often proposed by younger scientists or mavericks who are not invested in the previous paradigm, their career does not depend on the success of the old paradigm, instead, their career could be made by the success of a new paradigm. Which scientists are part of a revolution will depend on their psychology - are they a risk taker, a lone voice, which social groups are they in, where do they work etc.?
It is not easy to challenge the accepted scientific views and new paradigms take time to establish. Often in the beginning, new paradigms do not explain all the evidence that the existing paradigm does, and it takes time to establish that the new paradigm fits with the evidence and solves some of the anomalies. A new paradigm also creates new problems that will become the new puzzlesolving of normal science.
How does this relate to cosmology? The normal day-to-day activity of cos- mologists is working within the ACDM model of the evolving universe, this is the current paradigm. The aim of our work is to extend the success of this paradigm by gathering more evidence from surveying the sky in greater detail. This is the 'puzzle-solving'. Although there are anomalies in the ACDM model, cosmologists do not abandon it. The majority of working cosmologists are committed to the model and work on resolving the conflicts in the belief that the puzzle-solving activities will answer the problems eventually. The anomalies in the ACDM are increasing, resulting in more complex modifications to the model and an increasing number of scientists working on these anomalies. Using Kuhn's definition we can consider that cosmology is a ‘science in crisis’. A revolution is waiting to happen. So what is stopping it? As Kuhn said, an alternative paradigm is needed. At the moment, we have many ideas but to change the paradigm there needs to be one strong alternative that solves many of the anomalies of ACDM. That alternative is not there.
Kuhn followed in Bacon’s footsteps; he made observations on how science was being done, made conclusions from those observations and then wrote them down. Both philosophers used the basic scientific process to change how science is done.
Science within Society
As Kuhn so eloquently pointed out, scientists exist as part of a society that brings biases and intrinsic beliefs into science. So how do we make sure we are being scientific and that the work is being done in an objective way? Scientists work within the ethical framework of being honest in our work to ensure that it is carried out objectively, that the data is interpreted correctly and that the conclusions drawn are relevant and justified. This is policed by publishing the work so that others can test the science, repeat observations and validate conclusions. There is the added check of peer review. Before publishing a paper, or agreeing funding for a project, the work is reviewed by another scientist in the discipline who can confirm that the work has been done scientifically. We have scientific committees and funding bodies that apply ethics to what is funded and to how the research is done. These bodies have an essential role in science and society.
The scientific process is important, our society is based on the results of it so everyone has a part to play in it. Scientific education is key, not just about the knowledge but also the process itself. It helps the public to not be misled by false science, it helps society decide which science is funded and it helps science to be used in ways that enhances life for everyone.