Science and Objectivity …the quest for objective knowledge
Empiricism em·pir·i·cism n. 1. The view that experience, especially of the senses, is the only source of knowledge. John Locke (1632– 1704) Bishop George Berkeley (1685– 1753) David Hume (1711– 1776)
Problems with Empiricism l l A central tenet of Science is that all evidence comes via testable, experimental or empirical means and that scientific methods are an interplay between empirical evidence and testable conjectures. In this (somewhat innocuous use of the term) empirical = experimental In a more general vein, however, empiricism is a belief that all knowledge must arise from sense perception (no innate ideas). In this form empiricism is a description of how we know anything. But here is the “rub” – if knowledge comes only via sense perception then how do we “disentangle” ourselves from what we claim to know?
The British Empiricists l John Locke: No innate ideas – our minds are blank slates (“tabula rasa”) problem: how does our mind order and connect these sensations? How do we in science perceive and extend ideas? l Bishop Berkeley: the world exists only through our perception of it! This leads to idealism which asserts that only our ideas of things are real – not the things themselves l David Hume: All that we know of the world comes from perception and knowledge claims cannot be logically justified – they arise from “habits of the mind” problem: Is scientific knowledge nothing more than a collection of “habits of mind”? Don’t “many minds” come to shared conclusions – via empirical methods – that allows science to transcend this?
Why is the “Problem of Induction” a “problem”? l l l Hume’s “problem of induction” seems to be impossible to get around - to paraphrase Popper, Russell and many others it seems to put science on an irrational footing Doesn’t the success of science argue that there is something palpably different about the nature of scientific knowledge What, for example, do both Popper and Scheffler see as the “risk” facing science?
Scientific Objectivity l Israel Scheffler l Sees the very nature of science – its reliability and authority - at stake "The claim of science to represent a reliable body of knowledge rests four-square on the assumption of objectivity, on the assertion that scientists are not influenced by their prejudices or are at least protected from them by the methodology of their discipline. " William Broad and Nicholas Wade, Betrayers of the Truth (1985)
A FUNDAMENTAL FEATURE of science is its ideal of objectivity, an ideal that subjects all scientific statements to the test of independent and impartial criteria, recognizing no authority of persons in the realm of cognition. (pg 1) Since reason is, moreover, a moral as well as an intellectual notion, we have thereby been given also anew and enlarged vision of the moral standpoint … science has certainly provided us with new and critically important knowledge of man's surroundings and capacities, such enlightenment far from exhausts its human significance. A major aspect of such significance has been the moral import of science: its dynamic articulation of the impulse to responsible belief, and its suggestion of the hope of an increased rationality and responsibility in all realms of conduct and thought. (pg 4)
Recent attacks against this standard view have been launched from various directions. They have varied also in scope and precision, and their larger strategic import has not always been evident, even to the combatants themselves. Yet, taken together, these attacks add up, in my opinion, to a massive threat to the very possibility of objective science. Uncoordinated as they are, they have already subtly altered the balance of philosophical forces, exposing to danger the strongest positions of the objectivist viewpoint. (pg 12) The breakdown of observational community and of the community of meaning, and the consequent rejection of cumulativeness seem to remove all sense from the notion of a rational progression of scientific viewpoints from age to age. (pg 17)
But now see how far we have come from the standard view. Independent and public controls are no more, communication has failed, the common universe of things is a delusion, reality itself is made by the scientist rather than discovered by him. In place of a community of rational men following objective procedures in the pursuit of truth, we have a set of isolated monads, within each of which belief forms without systematic constraints. I cannot, myself, believe that this bleak picture, representing an extravagant idealism, is true. (pg 19) Bottom Line for Scheffler For science to “be science” it must be rooted in a realist view of the world that entails objective, value free knowledge claims. The “ideal of objectivity” is a limit point that coordinated scientific claims tend towards. While individual scientists may fall short of this the body of their cumulative work tends to this. Schleffler does not require certainty but he does claim a strong form of objectivity that will resonate with Popper’s idea of Third World Knowledge.
Sir Karl Popper l Tackles the problem of induction – claims to have solved it 'Hume's philosophy. . . represents the bankruptcy of eighteenth-century reasonableness' and, 'It is therefore important to discover whethere is any answer to Hume within a philosophy that is wholly or mainly empirical. If not, there is no intellectual difference between sanity and insanity. The lunatic who believes that he is a poached egg is to be condemned solely on the ground that he is in a minority. . ‘ Sir Bertrand Russell, A History of Western Philosophy (1946) The growth of unreason throughout the nineteenth century and what has passed of the twentieth is a natural sequel to Hume's destruction of empiricism. Bertrand Russell
Why is this chapter titled Conjectural Knowledge? OF course, I may be mistaken; but I think that I have solved a major philosophical problem: the problem of induction. (I must have reached the solution in 1927 or thereabouts. 1) This solution has been extremely fruitful, and it has enabled me to solve a good number of other philosophical problems. (pg 1) Popper agrees with Hume – you cannot, by logical means of argument, prove the Truth of a scientific claim … BUT You can disprove (by logical means) a scientific truth claim This has become a popular “definition” of what constitutes a scientific theory: A theory is scientific if it is potentially open to being disproved
How to Decide Among Theories We have seen that our negative reply to L 1 means that all our theories remain guesses, conjectures, hypotheses. Once we have fully accepted this purely logical result, the question arises whethere can be purely rational arguments, including empirical arguments, for preferring some conjectures or hypotheses to others. There may be various ways of looking at this question. I shall distinguish the point of view of theoretician—the seeker for truth, and especially for true explanatory theories—from that of the practical man of action; that is, I will distinguish between theoretical preference and pragmatic preference. (pg 13) We search for truth in theories by steadfastly “chipping away” at the falsifiable bits
Wait a minute! What IS a Scientific Theory Anyway? l A scientific theory is… l l l A collection of logically consistent statements that provide explanation of one or more observable phenomena Makes (falsifiable) predictions Has a deductive structure – by using a formal system of logic you can deduce outcomes by applying constructs of a theory
Example … Theory of Stellar Structure l Our modern understanding of how stars work l l l Energy production via fusion and other means Basic laws of physics lead to mathematical equations or conditions: l Hydrostatic equilibrium l Conservation of Mass l Conservation of Energy l Energy transport Makes testable predictions about how stars evolve!
l Doesn’t this prove theory of stellar structure? l l How would Popper address this Popper would likely conclude: l l l This is a good scientific theory in that it makes genuine, potentially falsifiable predictions, which it has – for the most – part passed It is not true – it must remain conjectural until it is proven false Just because it has passed many tests in the past does NOT make it a “better theory” (see pgs 18 -20) On the other hand, among theories actually proposed there may be more than one which is not refuted at a time t, so that we may not know which of these we ought to prefer. But if at a time t a plurality of theories continues to compete in this way, theoretician will try to discover how crucial experiments can be designed between them; that is, experiments which could falsify and thus eliminate some of the competing theories. (pg 15)
Pragmatic Preferences… In other words, there is no 'absolute reliance'; but since we have to choose, it will be 'rational' to choose the best-tested theory. This will be 'rational' in the most obvious sense of the word known to me: the best-tested theory is the one which, in the light of our critical discussion, appears to be the best so far, and I do not know of anything more 'rational' than a well conducted critical discussion. Of course, in choosing the best-tested theory as a basis for action, we 'rely' on it, in some sense of the word. It may therefore even be described as the most 'reliable' theory available, in some sense of this term. Yet this does not say that it is 'reliable'. It is not 'reliable' at least in the sense that we shall always do well, even in practical action, to foresee the possibility that something may go wrong with our expectations. (pg 20)
The Problem of Demarcation l How do you decide between scientific and other kinds of theories? l Falsifiability is the “acid test” - to be a scientific theory, a theory must contains the “seeds of its own destruction!” l Is Intelligent Design a Scientific Theory
Popper’s “Worlds of Knowledge” l l At the end of the day Popper is, among other things, questing after a form of scientific objectivity not unlike that of Scheffler Popper introduces 3 “Worlds” of knowledge: l l l WORLD 1: the physical world WORLD 2: the world thought and experience WORLD 3: the world of objective thought “…what I call 'the third world' has admittedly much incommon with Plato's theory of Forms or Ideas…” (Objective Knowledge; pg 106)
Let me repeat one of my standard arguments for the (more or less) independent existence of the third world. I consider two thought experiments: Experiment (i). All our machines and tools are destroyed, and all our subjective learning, including our subjective knowledge of machines and tools, and how to use them. But libraries and our capacity to learn from them survive. Clearly, after much suffering, our world may get going again. Experiment (2). As before, machines and tools are destroyed, and our subjective learning, including our subjective knowledge of machines arid tools, and how to use them. But this time, all libraries are destroyed also, so that our capacity to learn from books becomes useless.
WORLD 3 l The third chapter of OK is titled “Epistemology Without A Knowing Subject” In upholding an objective third world I hope to provoke those whom I call 'belief philosophers': those who, like Descartes, Locke, Berkeley, Hume, Kant, or Russell, are interested in our subjective beliefs, and their basis or origin. Against these belief philosophers I urge that our problem is to find better and bolder theories; and that critical preference counts, but not belief. I wish to confess, however, at the very beginning, that I am a realist: I suggest, somewhat like a naive realist, that there are physical worlds and a world of states of consciousness, and that these two interact. And I believe that there is a third world, in a sense which I shall explain more fully. (OK, pg 107)
My first thesis is this. Traditional epistemology has studied knowledge or thought in a subjective sense—in the sense of the ordinary usage of the words 'I know' or 'I am thinking'. This, I assert, has led students of epistemology into irrelevances: while intending to study scientific knowledge, they studied in fact something which is of no relevance to scientific knowledge. For scientific knowledge simply is not knowledge in the sense of the ordinary usage of the words 'I know'. While knowledge in the sense of 'I know' belongs to what I call the 'second world', the world of subjects, scientific knowledge belongs to the third world, to the world of objective theories, objective problems, and objective arguments. Thus my first thesis is that the traditional epistemology, of Locke, Berkeley, Hume, and even of Russell, is irrelevant, in a pretty strict sense of the word. It is a corollary of this thesis that a large part of contemporary epistemology is irrelevant also. This includes modern epistemic logic, if we assume that it aims at a theory of scientific knowledge. However, any epistemic logician can easily make himself completely immune from rny criticism, simply by making clear that he does not aim at contributing to theory of scientific knowledge.
My first thesis involves the existence of two different senses of knowledge or of thought: (i) knowledge or thought in the subjective sense, consisting of a state of mind or of consciousness or a disposition to behave or to react, and (2) knowledge or thought in an objective sense, consisting of problems, theories, and arguments as such. Knowledge in this objective sense is totally independent of anybody's claim to know; it is also independent of anybody's belief, or disposition to assent; or to assert, or to act. Knowledge in the objective sense is knowledge without a knower: it is knowledge without a knowing subject (pg 108 -109) In this we see Popper and Scheffler converge to a common idea of “value-free, pure objective knowledge”
Some parting thoughts on Popper l Popper rightly (I think) asserts that we do not “have observations - we MAKE observations” – in doing science our observations are theory driven It is theory that decides what we can observe. -- Albert Einstein l Popper (as was Sheffler) was deeply suspicious of subjectivism The subjective approach has made much headway in science Since about 1926. First it took over quantum mechanics. Here it became so powerful that its opponents were regarded as nitwits who should rightfully be silenced. (OK, pg 141)
Some Critical Scientific Experiments that challenge Realist Philosophies Critical Realist: I call’em as I see’m Naïve Realist: I call’em as they are! Anti-Realist: They ain’t nothin til I call’em!
"The temper of Realism is to de-antropomorphize; to order man and mind to their proper place among the world of finite things; on the one hand, to divest physical things of the coloring which they have received from the vanity or arrogance of the mind; on the other, to assign them along with minds their due measure of self-existence. " -- Samuel Alexander "The most acquisitive person is so busy re-investing that he never learns to cash in. 'Realistic people' who pursue 'practical aims' are rarely as realistic or practical, in the long run of life as the dreamers who pursue their dreams. " -- Hans Selye
Physics and Realism – Worlds in Collision! l l l Mathematization of the world Emergence of powerful “machine-metaphor” Discoveries in Physics challenge realist interpretation 1887 Hertz Photoelectric Effect 1687 1873 1800 1905 Math explosion! Calculus further articulated Differential Equations 1859 1900 Planck - Quantization 1905 -1925 Birth of Quantum Theory
Crucial Events l l l 1887 Heinrich Hertz confirms key prediction of Maxwell’s Electromagnetic Theory and, in so doing discovers the Photoelectric Effect 1900 Max Planck “discovers” quantization 1905 Einstein’s “Annus Mirabilis” – radically changes our notions of space and time and introduces concept of the quantum or particle of light (= photon) De Broglie - The wave-particle duality is unleashed! Bohr-Einstein debates – quantum “reality” is unlike naïve reality The EPR effect and Bell’s Theorem
Next Class Do Kuhn, Polanyi and Maxwell offer us a different way to look at science? l Can science still be both reliable and “objective”? l
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