In other words, even if there were such a thing as the correct theory of nature we lack physical capabilities to find out what it is for sure, distinct theories may well be empirically equivalent.
Duhem, Quine, and the Problems of Underdetermination The scope of the epistemic challenge arising from underdetermination is not limited only to scientific contexts, as is perhaps most readily seen in classical skeptical attacks on our knowledge more generally.
John Stuart Mill articulated a distinctively scientific version of the concern with impressive clarity in A System of Logic, where he writes: Most thinkers of any degree of sobriety allow, that an hypothesis In The Aim and Structure of Physical Theory, Duhem formulated various problems of scientific underdetermination in an especially perspicuous and compelling way, although he himself argued that these problems posed serious challenges only to our efforts to confirm theories in physics.
In the middle of the 20th Century, W. Quine suggested that such challenges applied not only to the confirmation of all types of scientific theories, but to all knowledge claims whatsoever, and his incorporation and further development of these problems as part of a general account of human knowledge was one of the most significant developments of 20th Century epistemology.
But neither Duhem nor Quine was careful to systematically distinguish a number of fundamentally distinct lines of thinking about underdetermination that may be discerned in their works. Perhaps the most important division is between what we might call holist and contrastive forms of underdetermination.
contrived, it may be very hard to procure the requisite evidence. The underdetermination thesis is much stronger. It asserts that in all cases, no matter how long and ingeniously evidence collection may proceed, the underdetermination will persist. (Merely) Sporadic underdetermination. The thesis does not merely assert that there can arise cases, either contrived or natural, in which some part of a theory . UNDERDETERMINATION THESIS, DUHEM-QUINE THESIS. Underdetermination is a relation between evidence and theory. More accurately, it is a relation between the propositions that express the (relevant) evidence and the propositions that constitute the theory. the underdetermination thesis What role can experimental evidence play in the acceptance of new scientific theories and in the reaffirmation of old theories?
Holist underdetermination Section 2 below arises whenever our inability to test hypotheses in isolation leaves us underdetermined in our response to a failed prediction or some other piece of disconfirming evidence. But contrastive underdetermination Section 3 below involves the quite different possibility that for any body of evidence confirming a theory, there might well be other theories that are also well confirmed by that very same body of evidence.
Moreover, claims of underdetermination of either of these two fundamental varieties can vary in strength and character in any number of further ways: As we will see in Section 2. In the sections that follow we will seek to clearly characterize and distinguish the various forms of both holist and contrastive underdetermination that have been suggested to arise in scientific contexts noting some important connections between them along the wayassess the strength and significance of the heterogeneous argumentative considerations offered in support of and against them, and consider just which forms of underdetermination pose genuinely consequential challenges for scientific inquiry.
For this reason, Duhem argues, when an empirical prediction turns out to be falsified, we do not know whether the fault lies with the hypothesis we originally sought to test or with one of the many other beliefs and hypotheses that were also needed and used to generate the failed prediction: A physicist decides to demonstrate the inaccuracy of a proposition; in order to deduce from this proposition the prediction of a phenomenon and institute the experiment which is to show whether this phenomenon is or is not produced, in order to interpret the results of this experiment and establish that the predicted phenomenon is not produced, he does not confine himself to making use of the proposition in question; he makes use also of a whole group of theories accepted by him as beyond dispute.
The prediction of the phenomenon, whose nonproduction is to cut off debate, does not derive from the proposition challenged if taken by itself, but from the proposition at issue joined to that whole group of theories; if the predicted phenomenon is not produced, the only thing the experiment teaches us is that among the propositions used to predict the phenomenon and to establish whether it would be produced, there is at least one error; but where this error lies is just what it does not tell us.
Although the outcome of the experiment was taken to show that light travels faster in air than in water,[ 3 ] Duhem argues that this is far from a refutation of the hypothesis of emission: But in condemning this system as a whole by declaring it stained with error, the experiment does not tell us where the error lies.
Is it in the fundamental hypothesis that light consists in projectiles thrown out with great speed by luminous bodies? Is it in some other assumption concerning the actions experienced by light corpuscles due to the media in which they move?
We know nothing about that. When the world does not live up to our theory-grounded expectations, we must give up something, but because no hypothesis is ever tested in isolation, no experiment ever tells us precisely which belief it is that we must revise or give up as mistaken: In sum, the physicist can never subject an isolated hypothesis to experimental test, but only a whole group of hypotheses; when the experiment is in disagreement with his predictions, what he learns is that at least one of the hypotheses constituting this group is unacceptable and ought to be modified; but the experiment does not designate which one should be changed.
It is simply not true that for practical purposes and in concrete contexts a single revision of our beliefs in response to disconfirming evidence is always obviously correct, or the most promising, or the only or even most sensible avenue to pursue.
So it seems that Duhem was right to suggest not only that hypotheses must be tested as a group or a collection, but also that it is by no means a foregone conclusion which member of such a collection should be abandoned or revised in response to a failed empirical test or false implication.
As noted above, Duhem thought that the sort of underdetermination he had described presented a challenge only for theoretical physics, but subsequent thinking in the philosophy of science has tended to the opinion that the predicament Duhem described applies to theoretical testing in all fields of scientific inquiry.
We cannot, for example, test an hypothesis about the phenotypic effects of a particular gene without presupposing a host of further beliefs about what genes are, how they work, how we can identify them, what other genes are doing, and so on.The underdetermination thesis has long been a truism in science studies, accepted and asserted with the same freedom that philosophers now routinely remark on the impotence of logic to provide us with a finite axiomatization of arithmetic.
must fail to determine uniquely a single theory. The thesis has a vener- able history, with roots extending as far back as Hume's skepticism over the possibility of justified inductive inference. The related Duhem-Quine thesis asserts that theories can only con- front evidence as whole.
Underdetermination and evidence. To show that a conclusion is underdetermined, one must show that there is a rival conclusion that is equally well supported by the standards of evidence. Underdetermination of theory by evidence, explored in great detail by Quine, means that from finitely many observations and measurements, that we are able to make by any point in time, even combined with perfect methodology, we are unable to determine a unique theory consistent with them.
quine home > underdetermination underdetermination Underdetermination is a thesis explaining that for any scientifically based theory there will always be at least one rival theory that is also supported by the evidence given, and that that theory can also be logically maintained in the face of any new evidence.
underdetermination of theory by evidence. Kitcher deﬁnes the transient un-derdetermination thesis as underdetermination of some theories by logic and currently available evidence. The permanent underdetermination thesis is the claim that some theories are underdetermined by all possible evidence acces-sible to scientists.