1. Department of
Department of Environmental Science
State University of Bangladesh
Masters in Environmental Science Program
ES 522: Environmental Analysis and Its
Interpretation
Lecture 1:
Epistemology and Scientific Methods
of Inquery

2. Lecture Outline:
 What is Epistolary?
 Concept of Rationalism and Empiricism
 Inductive and deductive Reasoning
 What is Science? What are the Scientific Methods of Inquiry?
 Scientific Methods in Action
 Standard Scientific methods
 Scope and Limitation of Scientific Knowledge

3. What is Epistomology?
Epistemology — branch of philosophy that deals with:
 what knowledge is?
 how we come to accept some things as true, and
 how we justify that acceptance.
The word is derived from the Greek words:
 “epistéme” “Knowledge”
 “logos” “study of” ---- “how we know”
Epistemology dealt with following fundamental questions:
 What is knowledge, and what do we mean when we say that we know
something?
 What is the source of knowledge, and how do we know if it is reliable?
 What is the scope of knowledge, and what are its limitations?
Therefore, Epistemology concerns itself with ways of knowing and how we
know.

4. Continuation…
The Nature of Knowledge
What is knowledge? ------- a justified belief
As Example:
We know X if, and only if,
 X is true;
 We believe X; and
 We are justified in believing X.
“Rationalism”
 Rationalism believe that logic is the
source of knowledge;
 Logical argument can be used to
derive knowledge if applied
properly.
Example:
 All psychologists are human.
 Some humans are women.
Therefore, some psychologists are
women.

5. Continuation…
Empiricism
 Empiricism believe that logic, connected to verification though observation
or experimentation that leads to knowledge.
 Uses observation or direct sensory experience to obtain knowledge
Problems:
 we can not necessarily
believe everything we see
(e.g. illusions)
 misinterpretation of
observation
 your perceptions can be
drastically altered by prior
knowledge, expectations,
feelings and beliefs
 Can be dangerous
Empiricism
Induction
Deduction
Generation of
principles and laws
in science.
Example: “When water is
heated in an open container, it
evaporates.”
Generation of
predictions in
science

6. Inductive and deductive Reasoning??
Deductive
Theory
Hypothesis
Observation
Confirmation
Observation
Pattern
Tentative
Hypothesis
TheoryInductive

7. Continuation…
Epistemology is closely connected to science.
Philosophy and Science
 Philosophy often interacts with science;
 Scientists are often confronted with the question, “How do you know?”
 Science is a way of knowing that requires a strong philosophical
underpinning (whether consciously sought of unconsciously learned).;
Knowledge versus Faith
 Science, sociology, history, and religion each have their own ways of
knowing and different types of certitude.
 Science refers a fundamental question on “how they actually know?”

8. What is Science?
Science is the ways of understanding the unknown
 It is organized
 It uses evidence to learn about nature
 It seek answers to questions about natural phenomena
 It explores scientific thinking and reduces emotional reactions.
The Goal of Science is …..
 To understand
 To Investigate
 To Explain

9. Scientific Methods of Inquiry?
Scientific methods of inquiry are ways in which a person can know things
or discover answers to questions
 Scientific Inquiry is only one epistemological approach to “knowledge”.
 Scientific inquiry is an way to assess the “Truth”
Forms of Scientific Inquiry
2. Discovery or Descriptive Science
 Observation
 Qualitative vs. Quantitative data
3. Inductive Reasoning
 Derive generalizations based on specific observations
4. Deductive Reasoning
 Specific predictions follow from general premise
1. Hypothesis-Based Science

10. Characteristics of Scientific Inquiry
 Asking & identifying questions
 Designing & conducting investigations
 Using appropriate technology & tools
 Formulating & revising explanations/models
 Analyzing alternative explanations/models
 Communicating results
 Generating new questions

11. 1. State the problem by posing a question
2. Makes observations
3. Forms hypothesis
4. Design an experiment
5. Collect, Record, and analysis
data/information
6. Draw conclusions
Processes of Scientific Inquiry
Consult prior
Knowledge

12. Continuation…
Firstly: Ask a question that can be answered by gathering evidence
Example:
 Which freezes faster, water or Salt water?
1. State the problem by posing a
question
2. Developing a Hypothesis
Secondly:
• A Hypothesis is a possible explanation for a set of questions
• Must be Testable
• Often written in an If….Then format
Example:
 If I add Salt to fresh water, then the water will take longer to freeze.

13. 3. Designing an Experiment
Thirdly:
• Test your Hypothesis by writing a step by step plan
• Control your variables
Example:
1) Controlled variable:
 Variables that stay the same for the whole experiment
2) Manipulated (Independent) Variable:
 The ONE variable that you can change on purpose
3) Responding (Dependent) Variable:
 What you measure to get the results.
Continuation…

14. 4. Collecting and Interpreting Data
Fourthly:
• Finding patterns or trend in your measurements
• Data is often organized in a table or graphs
5. Drawing Conclusions
Finally:
• Statements that sum up what you have learned from the experiment
• Includes a statement on if your data accepts or rejects your hypothesis
Example:
 Water containing salt freezes at lower temperatures than fresh water

15. Scientific Method in Action
We use the scientific method in everyday life
Example:
You got in your car to drive up here and turned the key but the car wouldn’t
start (observation)
Hypothesis: There is something wrong with the car
Predictions: battery dead, ignition problem, out of gas
Test predictions: turn on headlights, check spark plug wires, dip stick in
gas tank.
Analyze results: headlights work, strong ignition spark, no gas on dip
stick-gas gauge reads half full
Draw conclusion: gauge inaccurate, out of gas

16. Continuation…
Method of authority
 A person relies on information or answers from an expert in the
subject area
Problems:
 people sometimes assume that a person’s status as an authority
in one area transfers into some other area (e.g. athletes eating
cereals are not nutrition experts)
 authorities can be biased (e.g. psychodynamic vs. behavioral
psychologists)
 answers from an expert may represent subjective opinion rather
than true expert knowledge
 expert’s statements are often accepted without question
 just being called an expert does not make someone an expert

17. Standard Scientific Method (deductive logic)
The standard scientific method is a 3-part sequence:
 Logical deduction (starting with a theory about how the world
works)
 Developing clear, testable hypotheses
 Systematically collecting evidence (observing empirical data)
and testing these data to see if they support the hypothesis, and
hence the theory

18. Scope and Limitation of Scientific
Knowledge
 Scientific knowledge, are based on empirical evidence, cannot provide
answers to questions that do not have an empirical basis.
 Scientific knowledge cannot be used to make human value judgments;
 Some statements that scientists accept as correct at first appear to be
scientific but are not because they can be shown to be falsifiable.
 The verification process used in science is much more extensive.

19. Contract:
Shankor Paul
E-mail: shankor.paul@gmail.com
Cell: 01712009028;
FB ID & LinkedIn: Shankor Paul; Skype: Shankor_Paul