…whenever we find two philosophers who line up exactly opposite on a series of half a dozen points, we know that in fact they agree about almost everything.
Ian Hacking, Representing and Intervening
Ian Hacking’s statement above reflected his appraisal of the philosophers Rudolf Carnap and Karl Popper. Carnap a defender of induction and verification: a bottom-up approach to scientific truth in which one make observations then sees if these confirm or refute one’s theoretical statements; while the other, Popper, a defended deduction and falsifiability, a top-down approach in which one formulates theoretical conjectures then deduces the consequences through a process of testing to apprehend the truth or falseness of the conjecture. That both, as Hacking relates it, shared a common basis in scientific naturalism is both a marvel and a part of history.
Both thought there were distinct differences between observation and theory. Both believed the growth of knowledge is cumulative. Popper may be on the lookout for refutations, but he thinks of science as evolutionary and as tending towards the one true theory of the universe . Both think that science has a pretty tight deductive structure. Both held that scientific terminology is or ought to be rather precise. Both believed in the unity of science.
Yet, something happened after this, something changed in this baseline set of beliefs about the sciences and the naturalist approach these men shared. As Hacking reports it Thomas Kuhn in his now classic, The Structure of Scientific Revolutions, gave us a picture in diametric opposition to that naturalist universe of Carnap and Popper. For Kuhn the sciences were in disarray. There is no longer any sharp distinction between observation and theory. Science is not cumulative. A live science does not have a tight deductive structure. Living scientific concepts are not particularly precise. Methodological unity of science is false: there are lots of disconnected tools used for various kinds of inquiry. The sciences themselves are disunified.1
For Kuhn what most actual scientists are doing as compared to thinking in their work is puzzle-solving. As he states it both Carnap and Popper in their theories of science were in sum ways both wrong. “Normal science, sad to say, is not in the confirmation, verification, falsification or conjecture-and-refutation business at all (Kindle Locations 262-263).” Instead of either of these processes of induction or deduction what really happens is that anomalies accumulate to the point around a particular approach that the original theory or hypothesis no longer explains the phenomenon involved so that the actual scientists begin inventing new tools, ideas, or hypothesis to replace the outmoded science which Kuhn termed a paradigm shift or a scientific revolution that changes everything.
Kuhn was surprised at how his work suddenly brought about a sort of crisis in rationality within the scientific community. What Kuhn thought he was doing was exposing how certain points are reached through very real historical processes that allowed for scientists themselves to shift their allegiances from one scientific community to another a sort of conversion process. As Hacking describes it:
When you do buy into a theory, Kuhn continues, you’ begin to speak the language like a native. No process quite like choice has occurred’, but you end up speaking the language like a native nonetheless. You don’t have two theories in mind and compare them point by point – they are too different for that. You gradually convert, and that shows itself by moving into a new language community.(Kindle Locations 360-363).
So this touted paradigm shift is really a developmental and historical process ongoing relations within differing communities of the sciences as they develop other hypothesis and terminological frameworks, while slowly gathering others into that new fold who begin to use that new hypothesis and terminological framework within their own approach to a particular puzzle or set of problems.
Hacking quotes the work of Larry Laudan who influenced by Kuhn’s argument extended it to include seven basic classifications of this anomalous transformation of the sciences. First that scientific theories in transition are generally non-cumulative (i.e., neither the logical nor empirical content (nor even the confirmed consequences) of earlier theories is wholly preserved when those theories are supplanted by newer ones); second, theories are generally not rejected simply because they have anomalies nor are they generally accepted simply because they are empirically confirmed; third, changes in, and debates about, scientific theories often turn on conceptual issues rather than on questions of empirical support; fourth, the specific and ‘local’ principles of scientific rationality which scientists utilize in evaluating theories are not permanently fixed, but have altered significantly through the course of science; fifth, there is a broad spectrum of cognitive stances which scientists take towards theories, including accepting, rejecting, pursuing, entertaining, etc. Any theory of rationality which discusses only the first two will be incapable of addressing itself to the vast majority of situations confronting scientists; sixth, given the notorious difficulties with notions of ‘approximate truth’ – at both the semantic and epistemic levels – it is implausible that characterizations of scientific progress which view evolution towards greater truth-likeness as the central aim of science will allow one to represent science as a rational activity; and, finally, seventh, the co-existence of rival theories is the rule rather than the exception, so that theory evaluation is primarily a comparative affair. (Kindle Locations 379-391).
Hacking commenting on Laudan’s notions tells us that we need not subscribe to all Laudan’s points. As he says: “I share with critics a doubt that we can compare problem-solving ability. For me, Laudan’s most important observation is (point 5): accepting and rejecting theories is a rather minor part of science. Hardly anybody ever does that. I draw a conclusion opposite to Laudan’s: rationality is of little moment in science. The philosopher of language, Gilbert Ryle, remarked long ago that it is not the word ‘rational’ that works for us, but rather the word ‘irrational’.”(Kindle Locations 396-400).
I’m enjoying reading his history. As he tells us “I think that reality has more to do with what we do in the world than with what we think about it”.(Kindle Locations 424-425). Or as he says in another moment: “The final arbitrator in philosophy is not how we think but what we do” (Kindle Locations 618-619).
1. Hacking, Ian (1983-10-20). Representing and Intervening (Kindle Locations 219-226). Cambridge University Press. Kindle Edition.