• “The great difficulty is in trying to imagine something that you have never seen,

• that is consistent in every detail with what you have seen,

• and that is different from what has been thought of;

• furthermore it must be definite and not a vague proposition.” Feynman page 23

Thinking About Health & Disease: The Power of Epidemiology

• Example: causes of disease

• Florence Nightingale: a pushy rich dame who could count and knew the power of metaphor and men

• John Snow: an anesthesiologist who could imagine what he could not see and who could put pins in a map

Florence Nightingale

• Used a powerful metaphor to inspire people to do the right thing for the wrong reason

• Metaphor: disease as response to lack of harmony, organization, and cleanliness

• Common terms of early 19th century: miasma, contagion, fermentation

• Lack of doubt -- would have meant no role for the nurse

Definition of Disease

• “... the thing which strikes the experienced observer most forcibly... the symptoms or the sufferings generally considered to be inevitable and incident to the disease are not symptoms of the disease at all, ...

• of the want of fresh air, or of light, or of warmth, or of quiet, or of cleanliness, or of punctuality and care...”

What is Infection:

• I was brought up, both by scientific men and ignorant women... to believe that small-pox was a thing of which there was once a first specimen in the world which when on propagating itself...just as there was a first dog (or a first pair of dogs)

• With a little overcrowding, continued fever grow up, a little more typhoid fever.. typhus

19th Century Reasoning Revolution

• Formalistic philosophical assumptions

• Abstract reasoning• Belief in miasma,

damp, filth, lack of moral purity, or harmony as general causes of all disease

• Statistics• Disciplined

observations• Belief in specific

environmental causes for specific diseases

• Cause could reproduce indefinitely -- has to be living thing

John Snow & Broad Street Pump (1864)

• Observed both changes in human body with “Cholera” and changes across person, place, and time in cases of Cholera

• Epidemiological reasoning: clusters of cases around one pump, but also most cases got water from Southwark& Vauxhall

• Imagined an explanation

Signs of Cholera

• diarrhea, vomiting, and muscle cramps; possible coma and death

• 19th century scientists found increased amount of serum to solids and more acidity (gave unsterile saline injections)

• Snow observed intestine and saw changes that convinced him gut was source, not blood

Geographical Variation of Cases

• Map of London to show where two major water companies were located

• Snow walked around London and marked where cases occurred on a map

• Asked each household where they got their water

• Predecessor of the Odds Ratio

Odds of Getting Cholera

• Lambeth served 26,000 houses; 14 died

• Southwark & Vauxhall served 40,000 houses; 286 died– 14/26000=.000538– 286/40000=.00715– Odds ratio= .00715/.000538=13.3

Scientific Progress

• Koch discovered the Cholera Vibrio in 1883

• We have antibiotics and a vaccine

• We also have epidemics of Cholera that have swept accross most of Latin America infecting over 1,000,000 and killing 10,000

• Does the Cholera Vibrio kill?

• How can we interrupt transmission?

Transmission Mechanisms

• Waterborne– municipal water– putting hand in water vessel

• Food borne– street vendors’ foods & beverages & ices– leftover rice– fruits/vegetables

• Seafood -- uncooked and cooked

another quote

• “You have to permit the possibility that you do not have it exactly right.”

• “If you have made up your mind already, you might not solve it.” Feynman page 27

Feynman ch2

Religion: the way people believe about their religious beliefs

Most (natural) scientists do not believe in God

• they were taught? – No

• they know it all? – No

• they do not understand science correctly?

Belief in science and religion is consistent, but difficult

• It is valuable and necessary to doubt in science

• Conflict between partial facts of science and beliefs

• Science does not impact on moral conduct and ethical views

Religion is

• Metaphysical– what things are

– where they came from

– what man is

– what God is

– properties of God

• Ethical: how to behave• Inspirational:

motivates to act well, and inspire arts– science sometimes

conflicts with 1 and 2 (should not 2?)

Moral values (ethics) lie outside the realm of science

• conflicts (earth as center of universe) led to change in metaphysics, but no change in ethics

• Some practice Christian ethics without being Christian

• No external scientific evidence that the Golden Rule is good

• "Should I" has two parts– scientific: what will happen? (positive)– ethical: do I want that outcome? (normative)

illustrations: the importance of individuals vs the importance of the group(s)

• the Golden rule: individuals suffer voluntarily– uberimae fideii– public education

• First, do no harm– innovation in pharmaceuticals– genetic research

illustrations continued• Star Trek: The needs of the many vs, the

needs of the few.– welfare/redistribution– salary caps– life insurance premia

• smoking• sex• race• religion

– discriminate on basis of things under your control

illustrations continued

• Pareto improvement: Everyone at least as well off, and one party better– the notion of

externalities: safety, pollution

– theory of comparative advantage

• Max production if all resources allocated to one good

• in Elverum, 1C = .5T• in Mordor, 1C = 2 T

– these ratios are from a production frontier, not shown

Elverum Mordor

Trucks 5 4

Computers 10 2

• Let Elverum produce

more computers– = 4 computers, 3 trucks

• Let Mordor produce trucks– = 4 trucks, 0 computer

• Let Morder send 1 truck for 1 computer– M has 3 trucks, 1 C

– E has 4 trucks, 3 Cs

Elverum Mordor

Trucks 4 3

Computers 3 1

Elverum Mordor

Trucks 4 2

Computers 2 1

What happened?

• Because the relative costs of production were different, total (world) production rose through specialization and trade– more computers, and more trucks

• Called the “theory of comparative advantage.

illustrations continued

• Jesus improvement: Everyone better off, but one incredibly worse off– break up IBM– break up ATT– Microsoft???– deregulation?

Virtue as a basis for ethics

• Honor• honesty• integrity• temperance• fidelity• humility• patience

• Persistence• modesty• reliability• Loyalty• Recall Smith

– Prudence– Benevolence– Justice– Self-command

Value: The role of government

• Laissez Faire– Smith and the “invisible hand”

• Fiscal policy– John Maynard Keynes

• Monetary Policy– Milton Friedman

Western Civilization is built on two heritages

• humility of the intellect: "scientific spirit of adventure”

• humility of the spirit: Christian ethics

Russia v. US

• Suppression of ideas v. free ideas,