• Recap
• How to use weak severity
• Scientific Evidence and Diagnostic Frames
• Scientific Evidence and Prescriptive Claims
• Outline of Remainder of the Course

One main argument is:

Exercise of power involves someone else motivating us with reasons to do or think something else.

The reasons given to use greater enforcement powers involve claims:

• “most political violence is perpetrated by the left”
• “rhetoric from left-leaning organzations led to the assassination”
• “political violence is illegitimate”
• “US government should use investigations to target organizations producing the rhetoric that leads to violence”

Some of these reasons are empirical claims; some are normative claims

• diagnostic frames: there is a “problem” to be fixed.
• prescriptive claims: there is a “solution” we should use.

Scientific Evidence can only be used with empirical claims:

• “most political violence is perpetrated by the left”
• “rhetoric from left-leaning organzations led to the assassination”

• How do we check for scientific evidence?
• Is this useful?

When we are given reasons to do something (e.g. accept the use of police powers to target political rivals)

• claims diagnosing a problem
• claims prescribing a solution

involve value judgments. But they also involve empirical claims.

• We want to look at whether the evidence for the empirical claims was capable of showing those claims to be wrong
• We want evidence that has thoroughly checked whether the claim is wrong.

If the evidence we are given to accept power over us would always support the claims, even if the claims are false, we are not free. Bad evidence \(\to\) Bad reasons

weak severity requirement:

“one does not have evidence for a claim if nothing has been done to rule out the ways the claim may be false.”

“If data x agree with a claim C, but the method is … guaranteed to find such agreement, and had little or no capability of finding flaws with C even if they exist, they we have bad evidence, no test”

(Mayo 2018)

If evidence fails to meet weak severity requirement, it is not scientific (sniff test)

What leads evidence to not meet the bar of weak severity?

Common reasons are:

• Lack of transparency
• Unsystematic use of evidence (cherry picking)
• Failure to consider alternative stories (e.g., this evidence ALWAYS can be found)

What is the claim? What is the evidence? Meet weak severity?

What is the claim? What is the evidence? Meet weak severity?

White House senior advisor doubles down on voter fraud claims: “Voter fraud is a serious problem in this country” pic.twitter.com/DC6lVPQznz

— ABC News (@ABC) February 12, 2017

What is the claim? What is the evidence? Meet weak severity?

What is the claim? What is the evidence? Meet weak severity?

Claim: “US tariffs Worked, with little downside”

“scientific evidence”:

• does not mean the evidence is without flaw; does not mean that the claim is true
• refers to procedures and assumptions involved in generating evidence
• evidence seriously investigates whether claim itself or the assumptions underpinning the evidence are wrong

“unscientific evidence”:

• bad evidence does not mean claim is false.

Mayo (2018) also gives us:

strong severity sequirement:

“We have evidence for a claim C just to the extent it survives a stringent scrutiny. If C passes a test that was highly capable of finding flaws or discrepancies from C, and yet none or few are found, then the passing result, x, is evidence for C”

• evidence is scientific to extent it survives stringent scrutiny
• we have checked whether evidence relies on flawed assumptions
• considered whether evidence supports OTHER rival claims

Claims that there is a “problem” involve a value judgment and descriptive claims

• “political violence is bad” (a value judgment)
• “political left is perpetrating political violence”

Evaluating descriptive claims are relevant to “diagnostic frames”:

• How much political violence is there, really? (Compared to other violence)
• How much political violence is committed by the left? (As opposed to other groups)

• When people tell us there is a problem, there is a value judgement about what is good or bad. We can use scientific evidence to check whether this “problem” is real

Where can evidence for descriptive claims go wrong?

• How do we define what we are trying to observe? (What is “political violence”? Who is a “leftist”?) Can that definition be used objectively?
• What will we observe that correspond to these definitions? (What could we observe that counts as “political violence”?)
• How/What procedure will we use to actually observe these things?
• What could go wrong at each stage that would lead us to incorrectly conclude the claim is right (wrong)?

An attempt to motivate people to behave differently. An attempt to exercise power. Access to media outlets enables power.

(1) US is not experiencing (comparatively) high levels of immigration

• Lebanon (4.4 million people) has had more than 1 million refugees in less than 10 years (>25%)
• American (325 million people) has 44 million immigrants (13.7 percent)
• Rate of immigration to US has slowed over the past 10 years

(2) High immigration rates do not lead to political instability.

• Canada and Australia have populations that are 20 and 28 percent foreign-born, but no major political problems

(3) New immigrants are employed at high rates.

• Unemployment among immigrants is lower than native-born Americans
• not a burden on state provision of social services

(4) Lower immigration slows economic growth

• Fertility rates among native-born Americans are dropping
• Because of that, future workforce will be smaller, productivity will be less, growth will slow

(5) America should admit 1 million more immigrants per year

• So growth rates can remain high

“Actually, the Numbers [Don’t] Show That”

\(\checkmark\) if science could test:

1. US is not experiencing high levels of immigration \(\checkmark\)

2. High immigration rates do not lead to political instability \(\checkmark\)

3. New immigrants are employed at high rates \(\checkmark\)

4. Lower immigration slows economic growth \(\checkmark\)

5. America should admit 1 million more immigrants per year

Even if 1-4 are true, what must we to assume to conclude that (5) is true?

prescriptive claims:

are normative claims that assert what kinds of actions should be taken

• hint: like a doctor or pharmacist, it prescribes a course of action.
• overlap with justifications/reasons given by power.

The basis for a prescriptive claim includes

• evidence supporting an empirical claim about the consequences of some action (causal claim)
• an assumption that some value judgment is correct.

(5) America should admit 1 million more immigrants per year

This is a prescriptive claim:

For it to be true…

1. What value judgments must we assume to be true?

2. What empirical claims must be true?

“Actually, the Numbers [Don’t] Show That”

“America should admit 1 million more immigrants per year”

Even if 1-4 are true: we need to assume that economic growth is desirable to conclude that (5) is true.

(5) America should admit 1 million more immigrants per year

scientific evidence cannot “prove” this claim

even if we evidence that is very capable of finding any flaws in claim that increasing immigration increases economic growth… (strong severity)

people who value cultural/ethnic homogeneity more than economic growth can’t be persuaded

You and your friends win a large sum of money in a lottery

You and your friends agree: you want to do the most good by donating the money.

You consider some options…

Which should you donate to?

• Option 1: Make-a-Wish (more Batkid, pls)
• Option 2: Mosquito Nets
• Option 3: Direct transfer of cash to impoverished people

Peter Singer and effective altruists say yes!

• we can evaluate which of these does the most good!

“Saving a child’s life has to be better than fulfilling a child’s wish to be Batkid.”

But wait, your friend says: experiments show that directly giving cash

• benefits the health, education, and life choices of children
• empowers women to be financially independent, escape abuse
• improve mental health

What should you do?

If you value minimizing suffering, but your friend values maximizing individual freedom…

then science cannot help us, because the disagreement is rooted in value judgements

“We should donate money for mosquito nets” is a prescriptive claim.

• Scientific evidence for empirical claim that “Mosquito nets (A) prevent malaria (B)”
  • NOT enough to conclude that does not imply “we should do (A)”: it depends on how we value B
• if we also accept value judgement that it reducing suffering is more important than maximizing freedom (or coolness)
  • THEN we can accept the prescriptive claim

Need to accept the causal (empirical) claim that \(A \to B\) AND a value judgment that \(B\) is good.

Science is still be helpful!

• If we assume less mortality is good (B) (a value judgment)
• What if science shows: mosquito nets don’t prevent malaria deaths. (empirical evidence)
• “A does/does not cause B” is informative!

Where can evidence for causal claims go wrong?

• What is causality?
• When and why might the relationship (correlation) between factors not be the result of causation
• What comparisons can we make to provide evidence of causation?
• What do these comparisons assume to count as evidence of causation?
• Is it possible that the evidence we are using could show a relationship that is not causal?

Learning to recognize what evidence is capable of proving claims wrong:

• how and why could evidence find support for a claim even if the claim is wrong
• what assumptions permit evidence to able to find claims to be wrong (when they are wrong)