Knowledge and Reality Lecture

November 2, 2011

Lewis and Causation

Couterfactual Conditional: conditional whose truth is not guaranteed by

the falsity of the antecedent [or the truth of the consequent]

•Conditionals where A is false in the actual world

•Involve not just the way things are, but the way things could be

Causation

•C causes e iff there is a chain

•Pushing a domino: pushing the first one is the initial event and

then it pushes the next one, and the next and so on till it ends

with the falling of the last one. Lewis asks if the pushing of the

first domino caused the falling of the last domino and Lewis says

yes because of the chain of events causing it

•Lewis says causation is transitive and causal dependence is not

•Transitive means that a causes b and b causes c, therefore a

causes c

The basic properties of relations ** question on exam

•A relation is what is expressed by a 2-place predicate

•Ex. X loves Y, X is taller than Y, X got here before Y did

•If you use one in a sentence, you will make a claim about both X

and Y

•Three basic properties:

oSymmetric: iff for all x and y in the domain; if X stands in

the relation of Y, then Y stands in the relation of X. Ex.

Sibling and being in the same room as someone. If

someone is your sibling, then they are your sibling. If

someone is in the same room as you, you are in the same

room as them. Being to the left of someone is not

symmetric

oReflexive: iff for all x in the domain. Ex. Being the same

height as himself and everything is identical with itself. You

will always bare your height to yourself. Can hold between

distinct things.

oTransitive: iff for all x, y, and z in the domain iff. Ex. Is

greater than [if X is greater than Y, and Y is greater than Z,

then X is greater than Z] or being an ancestor of [If John A

Macdonald is an ancestor of yourself and the second duke

## Document Summary

Couterfactual conditional: conditional whose truth is not guaranteed by the falsity of the antecedent [or the truth of the consequent: conditionals where a is false in the actual world. Involve not just the way things are, but the way things could be. The basic properties of relations ** question on exam: a relation is what is expressed by a 2-place predicate, ex. X loves y, x is taller than y, x got here before y did. Sibling and being in the same room as someone. If someone is your sibling, then they are your sibling. If someone is in the same room as you, you are in the same room as them. Being to the left of someone is not symmetric: reflexive: iff for all x in the domain. Being the same height as himself and everything is identical with itself. You will always bare your height to yourself.