EXPLANATION

Inference to the best explanation, another inductive inference

Explanations versus arguments: Arguments give us reasons to think

something is the case. Plausible or certain premise to uncertain conclusion!

Explanations give us reasons why or how something is the case. Uncertain premise to certain/known/factual conclusion/event

TYPES OF EXPLANATIONS

Procedural (how something is done) Interpretive (why something means

what it does) Functional (how something works or

functions) Theoretical (why something is the way

it is, why something happened)

THEORETICAL EXPLANATIONS

The focus of our analysis Pattern of reasoning: from premises about a

state of affairs (what we know to have happened) to a conclusion about why this happened.

Best Explanations: We often have competing, alternate, comparable

theories or explanations. We assess which is the best, most plausible,

most likely to be true.

PATTERN OF INFERENCE

More formally, the pattern: Phenomenon Q E provides the best explanation for Q Therefore, E is probably true

Informal: we do it naturally! When we evaluate whether is does

provide best explanation, we use criteria

PARTS OF EXPLANATION

Explanandum: what is being explained, the phenomenon Q

Explanans: the answer or statement that explains the explanandum

The explanans tries to explain the explanandum by positing or providing a theory

Sometimes requires imagination to formulate the theory

Theories expand our knowledge and enable it further

BEST EXPLANATION

Some basic starting points for determining which of several explanations is best If you formulate a new or novel one and do not

compare it to others, greater likelihood of it being false

If other explanations are just as good as yours, this sheds doubt on yours

If you study and research your explanation, greater likelihood that it will be plausible

OBSERVATION

We often observe our surroundings to determine which of any proposed theories is best

i.e., process of determining why your car won’t start. Battery dead Empty fuel tank Bad starter Vandalized, etc

PROCESS OF ELIMINATION

Using observation to eliminate theories Using background knowledge, if any Notice, we fill in premises to support

why any explanation is best

THEORIES

Used in all academic departments and many areas of life, courts, etc.

Organizing tools to help us understand Constructs, but not arbitrary Theories are inherently open to

revision, refutation and further confirmation

Theories are often causal (science)

SOME EXERCISES

9.2 p. 341 Perhaps first in 9.5

TESTING OR EVALUATING THEORETICAL EXPLANATIONS

Why do we need to determine which theory is better?

Minimal requirement: consistency Consistency must be internal and external Non-contradiction, non-opposition External consistency also includes

completeness! It cannot fail to include essential parts of explanandum

THEORY CHOICE, cont.

Minimum requirement cont. Incompleteness not effective when other

explanations are absurd Possibility of infinite number of

explanations (theory is “underdetermined”, evidence does not dictate what theory is best)

Quantity of evidence: a good indicator of which theory is better or best

ADEQUACY

If theory meets consistency requirement, it is eligible for further testing. If not, it can be scrapped! Careful: not refutational

The criteria for adequacy Testability Fruitfulness Scope Simplicity Conservatism

TESTABILITY

Requires that there is some way or method to determine whether theory is true or false.

Do all components of theory have to be testable, or only the whole theory?

Soul theory of personal identity, Plato Theory of witches, moral theory of

disease

TESTABILITY AND PREDICTIONS

Theories are testable when they make prediction of some event or effect or phenomenon other than event to be explained

Sometimes prediction can be a consequence or outcome

If theory does not do this or predicts the obvious, we have reason to doubt it. Novelty!

FRUITFULNESS

Theories are more adequate than others if they predict novel events or phenomenon

Fruitfulness also includes ability to encourage new research or open up new areas of research

Novel predictions: surprising ones! Karl Popper and criteria for genuine scientific

theories Einstein’s theory and its novel predictions: light

around objects appears bent due to curvature of space

SCOPE

How much does the theory explain or predict?

If one theory can explain and predict more than another, that theory is to be preferred over the other.

Explaining more diverse phenomena Newton’s theory explained more than

Aristotle’s, Einstein’s more than Newton’s, etc.

SIMPLICITY

Ockham’s razor and parsimony Theory which makes the fewest assumptions is to

be preferred over others Notice, comparative nature of theory choice. NO

GUARANTEES Conspiracy theories: too many assumptions which

require evidence I.E., creationism: assumes the existence of a

creator. But, simpler in other ways! Ad hoc or auxiliary hypotheses: simplicity is

compromised when these are added to “save” a theory

CONSERVATISM

A theory which contradicts or goes against our established knowledge or beliefs is more likely to be implausible

Background knowledge A warning against novelty! But… Claim: Vitamin C cures cancer! Claim: I have made a perpetual motion

machine, or I have produced cold fusion! Claim: Dowsing or Divining for water works!

SOME CAVEATS FOR CRITERIA

No strict formula. Sometimes one criterion is weighed more than others

Cannot be used to silence or discourage radical departures

Paradigm shift Criteria is not a proof, only a diagnostic

tool, requiring good judgement Non-subjective: judgement vs taste!

TEST OR T.E.S.T.

A fully assessment of which explanations is the best

At the end of the test, we must state which theory is the most plausible, the best…

A procedure that requires all the tools of critical thinking that we have examined

TEST, cont.

Step 1: State the theory and check for consistency

Step 2: Assess the evidence, either presented or not

Step 3: Scrutinize alternative theories. Step 4: Test the theory using criteria of

adequacy

STEP ONE

State theory in a clear, concise fashion Apply consistency test (is it eligible for

further assessment?)

STEP TWO

Evidence? What evidence is given? Is it reliable, does it commit fallacies, is the source credible, does it suffer from a causal confusion, is it consistent with background knowledge or specialized knowledge?

Is there evidence disconfirming the theory?

STEP THREE

Scrutinize alternative theories. Might have to formulate or look for

them (thinking outside box) Goes against our grain, our tendency

to identify with a favorite theory Using alternative theories for applying

criteria. If we miss this, we cannot take last step!!

STEP FOUR

Complete test by applying criteria of adequacy. Remember to apply all 5.

Examples on pages 364-68 are instances of response examples, how to apply the full test

Problem of background knowledge! How much can you be expected to know? Yardstick: what would you need to know to be

able to judge evidence or fully apply adequacy criteria.