How do we know?
James A. Van Slyke
How do we know?
 Different ways of obtaining knowledge and/or
Wisdom
 Science presents a specific methodology for
obtaining knowledge
 Unique method, but still has roots in philosophy
and other disciplines
A little philosophy …
 How do we know?
 Classic terminology – epistemology
 Epistemology
 Justification for knowledge
 Study of different methods for justification
 Science > Empirical observation
 Recording and observing different events
 Based on experience
 Related to logic
A little philosophy…
 Classic Metaphysics
 Explanations that go beyond the “physical”
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Mythological
Religious
Supernatural
Example – Plato’s theory of Forms
 Contemporary Definition
 Metaphysics as a worldview
 Overall explanation of purpose and meaning in the
universe
Hierarchy of the Sciences
 Different areas of explanation exist in a hierarchy
 Different branches of science explore different areas
of existence
 Each level of science is its own web of theories or
research programs
Metaphysics
Anthropology
Worldview;
meaning
and purpose
Integrative
Disciplines
Sociology
Complex
Systems
Psychology
Biology
Basic
Chemistry
Sciences
Physics
Building
Blocks
Christian Theology
Anthropology
Integrative
Disciplines
Sociology
Complex
Systems
Psychology
Biology
Basic
Chemistry
Sciences
Physics
Building
Blocks
Understanding Science
 Reduction
 Empirically investigating the parts to understand the
whole
 Reducing problem to a manageable situation
 Looking at a particular phenomenon from one level in
the hierarchy of science
Understanding Science
 Science studies natural explanations rather than
supernatural explanations for events
 Cannot provide a justification (pro or con) for
supernatural events
 Science does not make determinations based on
religion or faith, but on empirical observation
 The existence of God determined by metaphysics
(Theology) or Faith
Psychology as a Science
 Two contributing factors
 Human physiology
 Study of the nerves and tissues of the body
 Originally assumed that ‘spirits’ move the body
 Later demonstrated that electrical impulses move through
the nerves of the body
 Circulation occurs through blood flow throughout the body
 Body could be studied as a ‘natural’ object
 Neuroscience
 Pharmacology
 Stimulus and response
Psychology as a Science
 Two contributing factors
 Human Experimentation
 Germany Mid to Late 1800s
 Wilhelm Wundt (1832-1920)
 Helped create the first
psychology laboratory
 First to look at human
psychology experimentally
The Four Canons of
Science
 Determinism
 Empiricism
 Parsimony
 Testability
The Four Canons of
Science
 Determinism- assumption that the universe is
orderly. All events have meaningful, systematic
causes.
 Humans are very deterministic. We infer causality in
almost everything.
 Theories are statements about the causal relationship
between two or more variables.
Illusory Correlation
 Illusory Correlation
 The perception of a relationship where none exists
 When we believe two things are related, we are likely to
notice and recall instances that confirm our belief
The Four Canons of
Science
 Empiricism- The best way to figure out the orderly
principles of the world is to make observations.
Empiricism
 Originally supported by Aristotle in the 300s B.C.
 Really took off through the support of Descartes in
the 1600s.
 Became generally accepted in Philosophy by the
mid-1800s as the best way to learn about the world
and became one of the core assumptions of the
scientific method.
The Four Canons of
Science
 Parsimony- Scientists need to be frugal in developing
theories.
 When two competing theories do an equally good job of
explaining empirical observations, we should prefer the
simpler, or more parsimonious, of the two.
 Occam’s razor- principle of parsimony developed by William
of Occam during the 14th century
 Rube Goldberg- a comically involved, complicated invention,
laboriously contrived to perform a simple operation
The Four Canons of
Science
 Testability- Assumption that all scientific theories should
be testable using currently available research techniques.
 Falsifiability- idea that scientists should go beyond putting
their theories to a test by seeking out tests that could prove
their theories wrong.
 Operational Definitions- definitions of theoretical
constructs that are stated in terms of concrete, observable
procedures (e.g. hunger, fear, attention, etc.).
Five Ways of Knowing About
the World
 Intuition
 Logic
 Authority
 Revelation
 Observation
Five Ways of Knowing About
the World
 Intuition- direct perception of truth independent of
any known reasoning process
 judgments and decisions are based
on what “feels right.”
Five Ways of Knowing About
the World
 Logic- explicit reasoning that leads to sound
judgement
Five Ways of Knowing About
the World
 Authority- A person who holds expertise on a
particular topic or area of knowledge
Five Ways of Knowing About
the World
 Revelation- learning about something through
divine intervention
Five Ways of Knowing About
the World
 Observation- learning about something through
empirical testing