Thursday, 21 March 2019

Hypothetico-Deductive Method of Science

Prologue



              The philosophers of science have been engaged, for a long, with the question of the scientific method and the pattern of reasoning that leads to a scientific theory. Equally important has been the issue of discovery vs. invention of scientific theory. There has been a long-drawn debate over the true nature of the scientific method. The two most prominent versions that present the nature of the scientific method are the inductionist version and the hypothetical version.
                 The hypothetical method of science is popularly known as hypothetico-deductive method of science that considers the role of creativity, deduction and falsification or empirical verification as the cornerstone of the scientific method as against the simple observational and inductive process highlighted by the inductionists. 


Dialogue


What are the assumptions of Inductivism? 



     Inductionism in science is based on three assumptions viz:

  • Knowledge can be created by drawing inferences from a wide range of objective observations.

  • The observer (scientist) makes observations in a detached way i.e. he or she is not influenced by their personal assumptions, theories or beliefs while making the observations. 

  • All observations are done in a theoretical vacuum.

    What are the problems with these assumptions?


  The assumptions of inductivism are however considered as problematic. Two fundamental problems are raised against Inductivism. These are:

  • The first problem with Inductive Method is that observations are considered as highly objective venture and that scientists make observations in a theoretical vacuum.  Darwin highlights this problem when he says  in one of his letters that 

How odd it is that anyone should not see that observations must be for or against some view if it is  to be of any service" (Darwin, 1903, Vol 1, p.195).


  • The second challenge faced by Inductionism is popularly known as the “Problem of Induction”. We know that induction involves making inferences based on the large data collected through objective observations. It makes generalisations about some phenomena based on the observations. Now any such generalisation is never conclusive in Induction. However, large our data might be, it is never all-inclusive. Let’s see with an example.

        Based on observations it is generalised that all swans are white in colour. This 5generalisation is based on a large number of observations. However, yet not all swans have been observed. There is always a possibility that someday some black coloured swan might be observed. Even though the likelihood of such observation is very small, yet it can not be ruled out. This is popularly known as the problem of induction. 


Is inductivism totally rejected? 

       Thus simple induction is rejected as the normal method of science. Even though it is appropriate for simple scientific facts, it is ruled out as the means to arrive at complex scientific theories and explanations.

         Induction nevertheless plays a significant role in helping scientists come up with their bold conjectures. Even though observation is considered an essential aspect of scientific inquiry, the observation done is guided by prior notions of the scientist. Further, the generalisations arrived at involve more than simple induction from a large pool of observed data.



What are contemporary assumptions on the scientific method? 

             The contemporary belief is that all observations are theory laden. This means the scientists make guided observations. Observation do not occur in a theoretical vacuum and rather all observations are carried out against the scientists’ preconceived notions or assumptions or personal theories.

        Science make leaps througthe intervention of the scientists’ prior theories or preconceived notions that in turn influence their decision regarding observations to be done. 


         Why is the term hypothetico used in HD Method? 


           According to Christian Huygens, the construction of a scientific theory begins with scientists' bold conjecture(s).  where conjectures are sort of explanations for some phenomenon. These conjectures are hypothetical in nature. 

         According to Whewell, all scientific theories begin with a hypothesis. The hypothesis is a conjectural statement about the relationship between two or more variables. This hypothesis is assumed to be a generalised statement that is created by the scientist to explain some phenomenon and is assumed to explain a wide range of observations It’s a bold gesture from the scientist based on their personal theories and preconceived notions.

       The creation of scientific knowledge begins with the scientist's conjecture (Hypothesis) which is an outcome of the creative ability of the scientists to "synthesize, to relate, and to formulate new conceptual structures" (Velasquez, 2007, p.227). 


           Whewell, further argued that                    

"Our hypotheses ought to foretell phenomena which have not yet been observed...    the truth and accuracy of these predictions were a proof ..  that the hypothesis was…..  valuable and, at least    to a great extent, true.                                                                       (Whewell 1847, 62-63).


Thus the scientific method is assumed to be hypothetical rather than inductive as was popularly presented.


Why us the term deductive used in HD Method?

        The creation of scientific knowledge initiates with a bold conjecture or a hypothesis. The conjectural statement of the scientist which is also considered as the personal theory of the scientist or hypothesis is presented initially in broad terms and is yet to be validated. 

     The initial broad conjecture proposed by the scientist is considered a Tier I hypothesis that is to be tested and validated empirically. This Tier I hypothesis is taken as an assumption and the scientist deductively reason and deduce logical consequences from it.

         The Tier-I hypothesis is a broad statement. To validate it or to test the validity of the statement,  the scientist deduce logical consequences from this broad statement that can be tested against the canons of empiricism. 

        To establish the veracity of the hypothesis, the scientist makes certain predictions from the hypothesis (Tier-I) through deductive reasoning. The deductions thus arrived at are also hypothetical and constitute the Tier-II hypothesis.

        The Tier-II hypothesis arrived at through deduction, is empirically verified. The confirmation of the Tier-II hypothesis validates the Tier-I hypothesis.

   Thus it is the verification of deductions arrived at from the hypothesis that a scientific theory is established, modified or dropped down. Thus Claude Bernard (1865) explicitly claimed that his methods involved two distinct phases viz. inventing a verifiable hypothesis and then testing the same.

       Thus the term deductive is justified in the name of the scientific method i.e HD Method.


If hypothesis and deductions are the key processes in the scientific method then why do we say scientific theory is empirically embedded?


    HDM involves a two-tier system of hypothesis (Trotta, et., al., 2013). A more general hypothesis is hierarchically created at a higher level to explain a certain set of observational data. At the second level in the hierarchy, there are one or more hypotheses that are deductively created as consequences considering the hypothesis at level one to be true. 

    The Tier-I hypothesis is validated through the validation of the Tier-II hypothesis. However, the Tier-II hypothesis is validated empirically. The deductively arrived consequences (or Tier-II hypothesis) are subjected to further observation and experimentation to verify them. 

       The necessity of empirical verification of the deduced consequences from the hypothesis makes scientific theories empirically embedded.  




What are the steps of the H-D Method?

               a. Hypothesising


Scientists faced with some explanation problem make a bold gesture and propose a hypothesis as a tentative explanation for some set of observational data. 

       b. Deduction


The hypothesis is taken as a true premise and following deductive reasoning, the scientist makes certain predictions. These predictions are logical consequences if the tier I hypothesis is taken to be true. The predictions are themselves hypothetical statements (Tier-II). The Tier-II hypothesis or the predictions or consequences emanating from the Tier-I hypothesis are more specific.

    c. Observation


The tier II hypothesis is empirically tested i.e. the consequences deduced need to be examined against the real-world processes. The observational data decides the fate of the tier I hypothesis- whether it is to be accepted as a theory, modified or discarded. 


The three-phase scientific method termed the hypothetico-deductive method (HDM) shows the hypothetical nature of SM. 

    The general pattern of reasoning goes like this:





Friday, 15 March 2019

Thomas Kuhn and Theory of Scientific Revolution:

Thomas Kuhn and Theory of Scientific Revolution:

Prologue
Every discipline is characterized by both stability as well as change. Stability in the discipline helps it to consolidate its theories and presuppositions whereas change brings in dynamism in the discipline and allows itself to enrich, expand and evolve. Philosophers of science are often concerned with the process by way of which change-termed as conceptual change by Toulmene, takes place in the discipline of science. There are different theories –that given by Collingwood, Thomas Kuhn and Toulmene. Thus the Structure of Scientific revolution by Thomas Kuhn is basically a theory of conceptual change in the discipline of science.

Dialogue

What are the key concepts included in Kuhn’s Theory?
To comprehend Kuhn’s theory, one need to be very clear about two key terms or concepts. The two key terms or concepts are
i. Paradigm
ii. Revolution

How can we interpret the term Paradigm?
According to Kuhn, during a given period of time, there exists a fundamental theory in science that is accepted by the community of scientists. The scientific community, accepts the theory and are engaged in further exploration, elaboration and consolidation of the theory. New applications are searched for the theory and the community, as a whole, adheres with the fundamental theory and its validity. Kuhn considered a paradigm as a way of thinking and acting that is accepted by the community of scientists who work under the guidance and standards of the existing paradigm.
Toulmene characterize Paradigm as a ‘set of presuppositions’ or a constellation of concepts along with a set of assumptions and procedures that together constitute a paradigm or a world view.

Is Paradigm permanent or it changes?
No changes do occur in paradigm and such change accounts for the conceptual change and development of the discipline of science.

Why and How do this change takes place?
Most of the time in the discipline of science, the community researches and explore answers to their questions under the guidance of the existing paradigm that they accept. This period is considered by Kuhn as the phase of Normal Science during which the scientists are able to explore new applications of the theory and the observations are satisfactorily explained by the paradigm.
However, certain observations emerge that could not be explained by the existing paradigm. Thus certain natural phenomenon could not be explained by the pre-Copernican theory. New theories emerges and many in the community affiliate with the new theories.  A sort of tension arises between different factions of scientific community adhering to the old and the new theory. The struggle between those who adhered with the Classical Physics and Relativistic physics is an example of such a tension.
This emerging tension eventually leads to a challenge to the fundamental assumptions and outlook of the existing paradigm. A sort of revolution takes place and the old paradigm gives way to a new paradigm.

What is scientific Revolution in Kuhn Theory?
According to Kuhn when the existing paradigm fails to explain several of the observations that arises during the normal phase, there arises a phase of crisis. Need is felt for a new theory that can explain the anomalies. When such a theory emerges, sort of tension arises between those who affiliate with the older theory and the new theory. Eventually, the new theory emerges full blown and it replaces the old one. A new world view with a new set of assumptions and outlook gets established and a new era of novel questions and researches arises. This change over was termed by Kuhn as a Scientific Revolution characterized by a shift in the paradigm.
For Kuhn, scientific revolution “are here taken to be those noncumulative developmental episodes in which an older paradigm is replaced in whole or part by an incompatible new one…”
What is the significance of Kuhn’s Theory?
Kuhn provided a new approach to view conceptual change in the discipline of science and hence explain the developmental process of the discipline. It also establishes the role of community of scientists in the conceptual change that occurs in science or for that matter in any other discipline.

Epilogue
Conceptual change is characteristic of any discipline including that of science. According to Kuhn, the conceptual change takes place through sort of revolution that Kuhn called as scientific revolution that leads to a change in paradigm that guides the research and inquiry in the discipline. A new theory emerges that replaces the older one and is able to explain the anomalies in observation that accumulated during the normal phase of science.

Sunday, 20 January 2019

Tuesday, 28 August 2018

Definng Criteria of Discipline

This blog presents a dialogue on what a Discipline is?


However before we understand it we need to know what is knowledge?

Knowledge, in its most popular form, is defined as a justified true belief. This definition is also as the tripartite definition of knoweledge since it include three important aspects viz.

                               i.    Knower S believes in something X.
                              ii.    X is true.
                             iii.   S's belief in truth of X is justified. The correspondence between X and its truth should not be merely a matter of coincidence.

However while accepting this definition of knowledge, one need to be clarified that this knowledge holds good for propositional knowledge only. There are other forms of knowledge as well such as procedural knowledge and tacit knowledge that could not be defined in terms of the tripartite knowledge unless they are all transformed in the form of propositions. 



How knowledge is confined into disciplines?

Knowledge is not fixed or limited either temporally or spatially. Ever since the onset of human civilization knowledge has been in a perpetual state of expansion and enrichment. The expansion of knowledge necessitate the need to organize the same in a way that it further facilitate communication and enrichment. 
     
      At a formal level, human beings have used the natural mental propensity to classify things as a tool to organize the vast array of accumulated knowledge. The classification of knowledge led to the emergence of various disciplines  and the basic purpose behind this classification was organization of knowledge so as to facilitate teaching, learning and research.

What are the conditions for a category of knowledge to qualify as a Discipline?

A review of literature can suggest a number of defining characteristics as qualifiers of a discipline. some of the significant qualifiers are provided below based on the ideas of Tanner and Tanner and Toulmene.
.

   a,  Guiding Problems:

         Every discipline has certain set of guiding problems or research questions. These pressing questions provide a direction for the development and progress of the discipline. The solution to these pressing questions further enrich the discipline in terms of its knowledge content.
         The guiding questions further serve as the uniting thread for those working or those affiliated to a particular discipline. People from far flung areas working on the problems are connected and linked with each other by their commitment towards finding answers to those questions. Thus a cohort of researchers is created in the particular discipline and many often the word discipline is used to denote this cohort of people working on the guiding problems of the discipline.

b. Epistemic Bases:

               Every discipline has its own distinct epistemic base in that the people involved in solving the problems of the discipline reflect a unity in their basic assumptions regarding how knowledge is to be created and validated. 

              The cohort of researchers in a particular discipline has certain basic assumptions and beliefs related to the epistemic questions of knowledge and they pursue their quest for knowledge in light of those basic assumptions and beliefs.

               Whereas this epistemic commonality is the basis for the unity among the members of the cohort, it many often also leads to contradiction and fraction that eventually culminates in a shift in the basic assumptions and beliefs (Thomas Kuhn). Nevertheless at any point of time there are certain well accepted beliefs and assumptions that the workers in the discipline stick to and act accordingly

c. Continuity: 

          At any given point of time every discipline is guided by a set fundamental questions that provides a direction for the progress of the discipline. However the fundamental questions at that particular point of time is linked to and arises from the fundamental questions that has guided the discipline in the past and it also paves the way for the fundamental questions that will arise and guide the workers in the future. 

      The relationship between the problems of the discipline at a given point of time in history of the discipline with those at other points of time in history was termed as Genealogy of Problems by Toulmene.

        It is this genealogy of problems that provides a continuity to any particular discipline.

. d. Dynamism:

       Every discipline is characterized by dynamism. The word dynamism signify that the discipline is in a state of flux and there is a perpetual growth and development in the discipline. however there are two views presented on the mode in which discipline grows and develops.

       First view is that of Thomas Kuhn as presented in his book  The Structure of Scientific Revolution. According to Kuhn, discipline undergoes a paradigmatic shift in which the basic assumptions regarding inquiry and the criteria of inquiry shifts leading to a sort of revolution in the particular discipline. Thus the fundamental approach towards the discipline's problem 
undergoes a complete change and a new era of research is initiated that leads to new achievements in the particular discipline.According to Kuhn then discipline develops through quantum leaps rather than following some gradual continuous process. 

      The second view was that presented by Toulmene according to whom enrichment and milestones in a discipline are achieved in a gradually evolving way. The discipline is persistently impregnated by a continuous flow of ideas of which the significant ones are selectively breeded whereas the inconsistent ideas naturally weed out by the self correcting inquiry process of the discipline. Toulmene's  idea was a result of his affinity with the theory of natural selection. The ideas that has greater scope in terms of explaining a phenomenon and accomodating the examples of the phenomenon are naturally selected, breeded and eventually established whereas the others keep on perishing owing to little explanatory power.




Friday, 24 August 2018

SCIENTIFIC ATTITUDE


UNDERSTANDING SCIENTIFIC ATTITUDE


To understand scientific attitude it is necessary to initially understand attitude, an attribute that belong to the affective domain of behavior.

According to Gordon Allport Attitude refer to a
                Mental and Neural state of readiness organized through experience exerting a directive or                    dynamic influence upon the individual’s response to all objects and situations with which it                  is related (1935, p..810).

As per Allport's definition then attitude involves

i. A Target:
                  The attitudinal target may be a person, an object, some situation event or even a phenomenon. The attitude is always directed to this target that is presented to the individual in form of a set of stimuli.
:
i. A Mental State:
                            The individual has a particular state of readiness whenever he or she is in vicinity of the attitudinal target. The mental state of readiness is a state that involves the individuals cognition, motivations and feelings in a combined way.

iii. A Behavioral Component:
                                               The state of readiness has a peculiar influence on the individuals potential response towards the attitudinal target. In general this response might be in form that reflects a favorable or an unfavorable disposition towards any or all the stimuli related to the attitudinal target.

iv. Source:
                The mental state of readiness or disposition towards the attitudinal target is a learned disposition. It arises through the individuals experiences and knowledge related to the attitudinal target. The knowledge and belief related to the attitudinal target represent the cognitive component of the attitude.







Based on the above discussion on Attitude, Scientific attitude is referred to as a special type of attitude that involves belief in certain tenets related to science and having the readiness to potentially behave or respond to any target in accordance to the beliefs. A concept map of the scientific attitude is presented as below:

CONCEPT MAP FOR SCIENTIFIC ATTITUDE
Add caption





ChiSquare Test

Chi Square https://docs.google.com/presentation/d/12d-tesJLFvRWe0S6McerPgghPcd_ctF16StvS-BFB8Q/edit?usp=drivesdk