January 26, 2021

Varieties of Claims

Plan for Today

1) Normative vs. Empirical Claims

3) Two Varieties of Normative Claims

4) Claims and Science

An Example:

(1) US is not experiencing mass 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 instability.

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

An Example:

(3) US labor market can absorb immigrants

  • Unemployment among immigrants is lower than native-born Americans

(4) Lack of immigration will slow US 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

POLL

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


  1. US is not experiencing mass immigration \(\checkmark\)

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

  3. US labor market can absorb immigrants \(\checkmark\)

  4. Lack of immigration will slow US 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?

“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.

  • And more desirable than ethnic homogeneity.

Varieties of Claims

Which varieties of claims/questions can be addressed with science?

Three dimensions

  1. Empirical vs. Normative
  2. Varieties of empirical and normative claims/questions
  3. Falsifiable vs. unfalsifiable

Empirical Claims

empirical claim:


is a claim about what is/exists or how things that exist affect each other.


The basis/evidence for empirical claims

  • consists of observation of the world.
  • no assumption about what is good/desirable.

Normative Claims

normative claim:


is a claim about what is desirable or undesirable.

  • assert what should or should not be.
  • “should” implied by the language of “right”/“wrong”
  • “should” implied by “too much”, “enough”, or “not enough” of something.
  • “should” implied by standards for what is “better”/“worse”

The basis/evidence for a normative claim:

  • must assume a value judgment about what is desirable/undesirable

Which are empirical? Normative?

  1. US is not experiencing mass immigration

  2. High immigration rates do not lead to instability

  3. US labor market can absorb immigrants

  4. Lack of immigration will slow US economic growth

  5. America should admit 1 million more immigrants per year

Normative Claims

Normative Claims:

value judgments:


are normative claims that

  • state what goal or ideal is “right” or “good”
  • or provide criteria/rules for judging what is “better” or “worse”.


They are not:

  • empirical claims for which the evidence is flawed
  • empirical claims that we can’t persuade someone to drop in the face of better evidence

Flat Earth!

Flat Earth?

"Vancouver is a city on the edge. It seems politicians and the police are unable, unwilling or incapable of stopping what has turned into a version of Dante’s Hell on the Downtown Eastside — illicit drug sales, open drug use, the stolen property bazaar, garbage, weapons, assaults, rape.

Vancouver no longer has a public health crisis that can be solved by needle exchanges, supervised injection sites, a naloxone-carting population, and pharmaceuticals substituted for illicit drugs. It is going to take more to solve the housing crisis by repurposing older hotels and simply putting roofs over people’s heads — a lot more.

Solving it requires bold leadership and a willingness to go beyond what has been done in the past, using evidence-based solutions that are in the best interests of all residents. Everyone deserves to feel safe, protected and respected, regardless of which neighbourhood they live in."

Prescriptive Claims

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.

The basis/evidence for a prescriptive claim includes

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

Revisit our Example

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

Value judgment? Prescriptive Claim?

Revisit our Starting Example

(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?

Revisit our Starting Example

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

This is a prescriptive claim:

Evidence will not “prove” this claim to everyone

e.g. people who oppose immigration to achieve cultural homogeneity value cultural homogeneity more than economic growth.

Science and Claims

Science and Claims

Empirical claims: can be evaluated using science

  • only need to assume that there is an objective world that we share
  • other assumptions about how we provide evidence of that objective world open to question
  • science is about prediction

Normative claims: cannot (fully) be evaluated using science

  • value judgments cannot be evaluated with science
  • prescriptive claims can only partially be evaluated with science

Another Example

Another example

We run the BCCDC. We have finite resources to allocate COVID-19 vaccines.

We all agree: we should aim to minimize deaths.

You disagree on how to distribute vaccines

  1. Plan A (Lottery)

  2. Plan B (Targeting communities with more infections)

  3. Plan C (Current BC CDC plan)

Discuss:

Which plan is best?

Can science tell us which plan we should adopt?

LINK

POLL

Another example

If we had Empirical Evidence on…

  • probabilities of death for different types of people (absent vaccine)
  • who would be more likely to get infected under different vaccine plans

Could assess which plan would yield the fewest deaths…

Another example

What if you value minimizing death, but I value maximizing equality?

Which plan should I support?

  1. Plan A (Lottery)

  2. Plan B (Targeting communities with more infections)

  3. Plan C (Current BC CDC plan)

  • Could the scientific evidence resolve our dispute?

Another example (Summary)

“My Vaccine Plan (X) reduces deaths (Y)”

  • Scientific Evidence that “X causes Y” does not imply “we should do Y”

  • Depends on how we value Y

But…

  • If we assume less death is good (a value judgment)
  • What if science showed: Vaccine Plan A (X) does not reduce deaths (Y). (empirical evidence)
  • “X does/does not cause Y” is informative!

Conclusion:

  1. Empirical vs Normative Claims
  2. Value Judgements
  3. Prescriptive Claims