The document discusses critical thinking and the uses of reason. It explores why people believe what they believe and notes that beliefs should be based on evidence, experience, and logical reasoning rather than indoctrination or common sense. It then outlines seven uses of reason: categorization, generalization, enumeration, inference, explanation, prediction, and criticism. The document also discusses arguments, which provide reasons to believe something, and explanations, which provide accounts for why things happen or are a certain way.

1. Science and Critical Thinking
George Matthews
Spring 2016

2. Why do you believe what you believe?

3. Why do you believe what you believe?
it’s
obvious
indoctrination
common
sense
authority
prior
exposure
motivation
evidence
experience
proof
explanatory
value
fits with
other beliefs

4. Why should you believe something?
it’s
obvious
indoctrination
common
sense
authority
prior
exposure
motivation
evidence
experience
proof
explanatory
value
fits with
other beliefs

5. the uses of reason

6. the uses of reason

7. the uses of reason
1. categorization: what kinds of things are there?

8. the uses of reason
1. categorization: what kinds of things are there?
2. generalization: what features do these things share?

9. the uses of reason
1. categorization: what kinds of things are there?
2. generalization: what features do these things share?
3. enumeration: how many of these are there?

10. the uses of reason
1. categorization: what kinds of things are there?
2. generalization: what features do these things share?
3. enumeration: how many of these are there?
4. inference: given this information, what follows logically?

11. the uses of reason
1. categorization: what kinds of things are there?
2. generalization: what features do these things share?
3. enumeration: how many of these are there?
4. inference: given this information, what follows logically?
5. explanation: why did that happen?

12. the uses of reason
1. categorization: what kinds of things are there?
2. generalization: what features do these things share?
3. enumeration: how many of these are there?
4. inference: given this information, what follows logically?
5. explanation: why did that happen?
6. prediction: what’s going to happen next?

13. the uses of reason
1. categorization: what kinds of things are there?
2. generalization: what features do these things share?
3. enumeration: how many of these are there?
4. inference: given this information, what follows logically?
5. explanation: why did that happen?
6. prediction: what’s going to happen next?
7. criticism: what’s wrong with this picture?

14. arguments and explanations

15. arguments and explanations

16. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?

17. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?
Arguments are attempts to justify beliefs by providing
reasons to believe them.

18. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?
Arguments are attempts to justify beliefs by providing
reasons to believe them.
What makes one argument more convincing than another?

19. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?
Arguments are attempts to justify beliefs by providing
reasons to believe them.
What makes one argument more convincing than another?
! Explanation: why did that happen?

20. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?
Arguments are attempts to justify beliefs by providing
reasons to believe them.
What makes one argument more convincing than another?
! Explanation: why did that happen?
Explanations are stories that try to account for why things
are as they are and do what they do.

21. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?
Arguments are attempts to justify beliefs by providing
reasons to believe them.
What makes one argument more convincing than another?
! Explanation: why did that happen?
Explanations are stories that try to account for why things
are as they are and do what they do.
Explanations might spell out the causes of things.

22. arguments and explanations
! Argument: given things we already hold to be true, what else
must we accept as true?
Arguments are attempts to justify beliefs by providing
reasons to believe them.
What makes one argument more convincing than another?
! Explanation: why did that happen?
Explanations are stories that try to account for why things
are as they are and do what they do.
Explanations might spell out the causes of things.
Explanations might say why things had to turn out as they
did given the initial conditions and the operative laws of
nature.

23. Which cards do you need to flip over in
order to test whether this rule is true?
All cards with an even number on
one side have a vowel on the other.

24. Which cards do you need to flip over in
order to test whether this rule is true?
All cards with an even number on
one side have a vowel on the other.
2 3 C A

25. Whose ID or drink do you need to check in
order to test whether this rule is being followed?
Nobody under 21 should be drinking beer.

26. Whose ID or drink do you need to check in
order to test whether this rule is being followed?
Nobody under 21 should be drinking beer.
17 23 beer soda

27. an argument

28. an argument
If modern biology is right, then all of life is one big
family tree and we are related to all other organisms
on the planet.
Modern biology is right.
So all of life is one big family tree and we are related
to all other organisms on the planet.

29. an explanation

30. an explanation
The force of gravity explains why it is that things fall
to earth, the tides rise and fall and the moon moves
across the sky every night.
This force is a universal attractive force between all
things with mass and it varies proportionally with the
inverse of the square of the distance between objects.