Science is distinguished from other academic pursuits because of its method. UNfortunately, there is not all that much agreement on what the method actually is or means…
Diagram taken from: http://www.beesource.com/pov/wenner/biossep1993.htm
Inductivist model of science
First introduced by Aristotle, the inductivist view is that a scientist observes at a whole lot of similar events or facts (evidence), and comes up with a generalisation that covers them (a scientific law). A major problem with this approach is that it assumes that facts are neutral things that are just given to us. They stand out without any need to have a theory under which they can be seen as facts ("the theory independence of facts"). Aristotle through that our access to reality was not mediated by anything- our observations and reality really did correspond (see correspondence theory of truth). However, when we identify facts in the world, we use some sort of theory to allow us to carve out some part of the world as a distinct fact. In other words, nature/reality is given to us as a unified whole, and how we cut it up depends on what how we are disposed to look at it. On the other hand, we also use a theory of some sort to group together a number of distinct events as facts that need a common explanation. As we move up in our level of abstraction, the way we group facts depends on the way we are disposed to categorize them. Our 'facts' are theory-dependent. Bacon's ideas were similar, although he also advocated the use of experimentation. This has similar difficulties- how we design our experiments, what we decide are acceptable results, how we create our hypotheses, the conclusions we draw from our experiments- all of these are theory dependent.
Verification (Carnap)
The main idea is that something is meaningful only if it can be verified. This is obviously a very important tenet in science (and in our criterion of truth, where something need to be public). Nonetheless, this seemed to be insufficient as an explanation of the scientific method. More importantly, there are a good many things that verification fails to address. It faces the concerns of coherence, ignores the theory laden aspects of our factual statements or our hypothesis-formation, and depends primarily on inductive logic. These difficulties led Karl Popper to establish Falsification as a model for scientific enquiry.
Falsificationism (Popper)
Popper was critical of induction as a means of finding truth. Instead, he though that a hypothesis, theory, or factual statement could only be scientific is it was falsifiable. For example, the hypothesis that "All human beings are mortal" would not be acceptable for Popper because it is impossible for us to go and check that every single human being will at some point die. Instead, it is only a scientific hypothesis if we can disprove it — thus "all human beings are immortal" would be a better hypothesis, because it can be falsified (by finding one person who died.) In other words, Popper wanted to get away from a view of science based on inductive reasoning and verification. Using falsification, we still use induction to generate a universal statement (no human beings are immortal), but accept that we will have to change our thesis when it is convincingly falsified—in this case, rather quickly.
When results are found which falsify the theory, a new theory must be found which can account for the discrepancies between our experimental data and our hypothesis. This new theory then becomes the dominant viewpoint until it is falsified in turn.
For example, Aristotle's theory of physics were falsified by Galileo, whose theory was itself falsified by Newtonian physics, which was in turn falsified by Einstein. When observation falsifies a previous theory, a new theory needs to be found which has greater "explanatory power" (explains both those things we could explain with the old theory and those we couldn't explain).
However, as Kuhn discovered through his study of the history of science, scientists often refused to accept results that falsified their theories; or they sometimes attempted to allow for exceptions in their theory that could essentially ignore falsifying results. Rather than accept that the earth-centric model of the universe was false, astronomers before Galileo resorted to rather fanciful descriptions of planetary model to explain the motions of other planets.
Science as Apprenticeship (Polanyi).
Michael Polanyi argued that the scientific method is not something that can be taught as a logical and rigorous process to be learned in textbooks (or philosophy books). Instead, science, and the scientific method, is learned through practice that is transmitted from teacher to student; Polanyi actually uses the terms master and apprentice, in reference to the guilds of medieval Europe. Because a crucial part of scientific knowledge is such that it cannot be spoken, fundamental aspects of the scientific method cannot be taught, but only demonstrated and imitated. (This is why we spend so much time doing labs).
In other words, the system of scientific knowledge is a social system of authority and apprenticeship, with its own codes of discipline and a strong emphasis on tradition, based on teaching expert skills. Science, like martial arts, cannot be learned from reading a book, nor can it be taught that way.
As a result, when experimental results first appear that seem to challenge the accepted framework or science, they are generally thought to be mistakes made by scientists or their equipment- not actual falsifications of the theories. "If every anomaly observed in my laboratory were taken at its face value, research would instantly degenerate into a wild-goose chase after imaginary fundamental novelties." (Science, Faith and Society, 2nd ed., University of Chicago Press, Chicago, 1964, p. 9) Thus according to Polanyi, scientists remain subjectively attached to preconceived hypotheses in the face of experimental results which seem contradictory.
Paradigm Shifts (Kuhn)
Tomas Kuhn's approach differed from those previously mentioned by his reliance on the history of science. In his work "The Structure of Scientific Revolutions" he argued that science does not progress by a linear accumulation of new knowledge, but undergoes sudden revolutions, which he called "paradigm shifts." When one such paradigm shift occurs, the way research is carried out within a particular field is abruptly transformed. Rather than seeing science as the consistent building of truth upon old truths, sometimes discarding those that has been falsified, Kuhn offered an explanation of scientific progress more akin to punctuated evolution than graduated evolution.
According to kuhn, scientific progress and research was marked by the interplay between two stages: normal science, and paradigm shifts. When the paradigm which structures scientific research is unchallenged, normal science takes place. During this time, most results which do not conform to the paradigm are not see as refuting the paradigm, but as the mistake of the researcher. (popper has a heart attack here). This resistance to the attempted refutation of key theories means that revolutions (paradigm shifts) are not sought for except under extreme circumstances. However, when the number of "falsifying" results accumulates and can no longer just be ignored, science reaches a crisis. The solution to this crisis is the creation of a new paradigm, which subsumes the old results along with the anomalous results into one framework.
When there is a crisis but no satisfactory paradigm to replace the old model, the battle between ideas is all the more obvious. Competing schools of thought use different procedures, theories, even metaphysical presuppositions. Scientific progress slows because a lot of intellectual energy is put into arguing over the fundamentals with other schools of thought instead of developing a research tradition. Eventually, some schools of though offer more successful models or ways of approaching the fundamental problems of the old paradigm. This success draws away adherents from the other schools, and a widespread consensus is formed around the new way of defining the problems and their solutions. This can be seen clearly with the current debates surrounding string theory.
Methodological anarchy (Feyerabend)
Moving even away from a coherent account of the nature of science and scientific discovery, Feyerabend claims that new theories came to be accepted because their supporters made use of any trick available to advance their cause. In other words, scientific theory are not accepted because of their accord with a scientific method, but because the proponents of a given theory were more convincing or conniving than others. He insists that there should not even be any fixed ideology which we use to define science or scientific progress. Great scientists are methodological mercenaries- using whatever method is available that will best allow them to search for truth.
Because there is no scientific method, science therefore does not have any reason to make the pretentious claims of a priviledged access to truth. Science then, according to Feyerabend, is one way of discovering truths, and is only considered the best because it is assumed to be so from the outset. Another interesting aspect of his view of science is the insight that science isn't one thing, but many. That is, scientific research is not a monolothic process, but rather a patchwork of various and asunder attempts to find answers or explore questions, not all of which begin with the same assumptions or even use the same methods.
Science as Process (Atkinson)
Atkinson provided a thought that completed the picture for us. An individualistic (creative) scientist generates some new perception about nature when in the exploration mode (lower right corner), often after having observed an anomaly in a set of results during the progress of "normal" science. Recognition of that anomaly permits a transition from an attitude of "Realism" to "Relativism" - an interpretation considered ''fact '' before is recognized as perhaps no longer adequate to explain known facts. That scientist then "creates an image" (in Atkinson's words) - forms an alternative explanation - and attempts to convert others to the same point of view.
If others can be convinced, that scientist (perhaps others as well) may try to verify the find (lower left corner of the diagram) - a very necessary part of the process. For many, adequate verification may suffice to establish "truth,'' but others might insist on a test of the hypothesis and move either to the upper left corner of the diagram (falsification approach) or to the upper right corner (inference approach) and test the hypothesis.
(http://www.beesource.com/pov/wenner/biossep1993.htm)
