Some Issues to Consider Some Issues to Consider in thinking about in thinking about

Causes and ExplanationsCauses and Explanations

Issues in Causal AnalysisIssues in Causal Analysis

• Limitations of traditional, single-causal models in dealing with non-communicable disease which have many, interconnected causes

• There are many conceptions of causation itself

• Statistics refers to probability and chance, but what do these actually mean? How do we deal with uncertainty?

• Levels of explanation: the How vs. the Why?

• Are we using the right mathematical basis?– Complexity & chaos theory; non-linear relations; fuzzy logic, etc.

EpistemologyEpistemology• The theory of knowledge: what is

knowledge and how is it acquired?

• How do we know that we know what we think we know? Etc.

• Bases of knowledge:– Metaphysics– Positivism– Post-positivism

MetaphysicsMetaphysics• Deals with knowledge that cannot be

reached through studying material reality– Nature of the mind & ideas– Unverifiable

• But science alone cannot explain reality– Scientific ideas are continually replaced by

newer ones– “Truths” are not final– Human interpretation is variable

PositivismPositivism

• Rejects metaphysics– Focuses on observable & measurable– Thoughts are irrelevant because

unmeasurable

• Mechanical– Cause & effect– Seeks to predict & control the world

Post-positivismPost-positivism

• Rejects positivism

• Knowledge is not based on solid foundations; it is conjectural– We may assert ideas but these can be

modified in light of further investigations– We cannot take a fully objective point of view– Context is important– The closest we can come to proof is to try but

fail to reject a hypothesis.

Nomothetic & IdiographicNomothetic & Idiographic

• There is a spectrum of sciences from hard to soft; different approaches to causation in each

• Especially: generalising vs. particularising traditions:

– What is the purpose of science: to derive general laws, or to explain individual cases? (Nomothetic vs. idiographic sciences)

– The approach to causal thinking is different in each, and medicine is in both camps

Categories of explanationCategories of explanation

• Scientific explanations (theory is central)

• Narrative (describes what happened)

• Historical (explains specific events)

• Teleological (the purpose or reason)

• Everyday (usually the “why” questions)

• Magical, religious (are these really explanations?)

Two traditionsTwo traditionsAristotelian• To make facts

teleologically understandable

• Applied to actions & intentional agency

• “Why?” questions• Used in human & social

sciences

Galilean• To explain & predict• Commonly applied to

events• Causal mechanisms• Generally “how?”

questions• Used in natural

sciences

Both seem relevant to medicine…

Holism, reductionism & Holism, reductionism & complexity theorycomplexity theory

• Basic question of whether a complex whole (e.g., your mind) can be understood in terms of functioning of its parts

• “Holism” argues that the whole cannot be understood by analyzing parts; “why?” & “how?” are distinct

• “Reductionism” says that laws governing the whole can be deduced from laws governing the parts, plus laws concerning relations between the parts

Sources of explanations for social Sources of explanations for social epidemiology epidemiology

• Social sciences – sociology

• Behavioral science

• Psychology, personality, etc.

• Combined psychological + biological (e.g., psycho-neuro-immunology)

• What about history?