Sociology Index

HYPOTHETICO-DEDUCTIVE MODEL OF SCIENCE

The hypothetico-deductive model of science is the classical or traditional model of how science operates: scientists are assumed to begin with a theory, deduce a hypothesis from the theory and then gather evidence to test the hypothesis.

In hypothetico-deductive model of science if the hypothesis is confirmed the theory is assumed to be correct or useful. Weber rejected the hypothetico-deductive model of science.

One of the most influential accounts of epistemology in the philosophy of science is the hypothetico-deductive model, and any discussion of the hypothetico-deductive model requires a discussion of the deduction of empirical consequences from theoretical statements.

Even Carl Hempel realized early on (in a preliminary way) that the 'deductive' half of the hypethetico-deductive model is not as deductive as the name implies. (Hempel, 1966, p.31). In standard hypothetico-deductive, bootstrapping and Bayesian accounts of confirmation, idealizations and approximations are simply ignored.

Philosophy and the New Archaeology - by Paul Newall - galilean-library.org/newarch.html
Binford advocated Hempel's hypothetico-deductive model – that is, offering an explanatory hypothesis, deducing its consequences and testing for them – even though it was quickly shown to be flawed. The most common example used in this context is a proposed law such as "all swans are white"; if true, it would follow straightforwardly that all swans are white, but in order to confirm this we would have to check all swans – so it can never be confirmed deductively. In archaeological terms, this would be much like explaining the collapse of civilisations by a specific set of circumstances: in order to confirm that we have a law, we would have to check all civilisations anywhere and at any time. The hypothetico-deductive model can thus only apply in restricted (usually trivial) domains.

"A common understanding of science is that:
� Progress occurs through a process of falsification.
� Incorrect theories are rejected on the basis of empirical evidence.
� Overtime this culminates with correct theories remaining in place.
According to this understanding, scientific research ought to adhere to the logical and empirical procedures outlined by the hypothetico-deductive model of science.
1. So according to this model, scientists commence their research activity with a theory about the nature of the world.
2. These theories are then submitted to empirical tests deriving hypotheses about particular observations.
3. An inductive logical phase then ensues, whereby the findings are interpreted and the theory adjusted to fit the newly discovered facts.
Criticism of the model.
The main problem with subscribing to the hypothetico-deductive method as a complete explanation of the way in which science works is that it disguises the ‘perspectival’ nature of the knowledge it produces.
The scientific truths produced through the hypothetico-deductive model are perspectival and bound to a particular paradigm." - J. NGUNYI WAMBUGU - psychology.unp.ac.za

The Hypothetico-Deductive Method: 
The ideal method for science, according to this model, would seem to be purely deductive, starting with observations statements directly tied to experience and deducing general laws according to the laws of logic. This ideal, however seems to have two problems, both recognized by the logical empiricists:
1. This isn't the method scientists actually use. They have general laws or hypotheses ahead of time and test them in carefully designed experiments.
2. The problem of induction: There seems no way to logically deduce general statements from a number of particular statements. No matter how many white swans you see, you can't deduce, or induce, that all swans are white, because there may be some group you haven't been exposed to yet. There is no satisfactory logic of induction.
Thus, to accord more with actual scientific practice and to put aside the problem of induction, the hypothetico-deductive model of science was devised.

The Hypothetico-Deductive Model 
Another approach to verifying the truthfulness of statements about reality is to assess them as logical conclusions of laws established a priori through the human experience. The Hypothetico-Deductive (HD) model, in effect, admits that the rules of positivism are impossible to follow--that objective, value-free, unbiased observations are impossible to obtain. The HD approach is to establish a set of rules whereby objective, value-free, unbiased conclusions can be drawn from admittedly biased observations. 
In the HD model, the explanandum (event to be explained) is a conclusion drawn from premises (explanans) that cover one or more universal laws. 
The HD model takes the following form: 
Law: Always, if A then B.
Observe: A.
Then: B. 
For example: 
Law: All men are mortal.
Observe: Socrates is a man.
Then: Socrates is mortal. 
The Phenomenological Critique of the HD Model 
The HD model allows for symmetry of explanation and prediction, but suffers from two fundamental problems: 
The Problem of Deduction 
The Problem of Induction - soc.iastate.edu/Sapp/Science.html

Why medicine still needs a scientific foundation: restating the hypotheticodeductive model - part one
The hypotheticodeductive model of science provides both a coherent description of the growth of scientific knowledge and a prescription for the conduct of good science.

Why medicine still needs a scientific foundation: restating the hypotheticodeductive model - part two
Kevork Hopayian
British Journal of General Practice, 2004. May 1; 54(502): 402–403. 
Many contemporary criticisms of science and medical science are based on false characterisations of the scientific method and on imprecise usage of the terms linearity, reductionism, and positivism. The alternatives can sometimes fall into the traps the scientific method was developed to avoid. The hypotheticodeductive model does not deny the value or meaning of other disciplines, but it does clearly demarcate what constitutes the scientific method from others. It doing so, it provides both a coherent description of the growth of scientific knowledge and a prescription for the conduct of good science.
The hypotheticodeductive model is very different to positivism. If any ‘-ism’ is to be applied to science it should be realism: the belief that science aims to discover how things really are and while it can never fully reach that goal, science constantly progresses towards it.
The social behaviour of individuals is not discordant with the hypotheticodeductive model because all individuals, whether scientists, lawyers or politicians, will want evidence that backs up their prior beliefs. What matters is what happens to the theory when the evidence is found rather than what motivated its collection.

Rules of engagement in the hypotheticodeductive model
Kevork Hopayian, General Practitioner.