Science: Some Basic Concepts

• Author: Alan D. Gold
• Pages: 79-123

Chapter

4:

Science:

Some Basic Concepts

GIVEN

that

the

rules

of

admission

and

valuation

of

expert evidence have

come

to be

grounded upon

the

scientific

method

as the

only demonstrably

valid

and

reliable foundation that

can

consistently save

the

justice system

from

beguiling

but

worthless, fallacious,

or

misleading "expertise,"

the

time

has

come

to

focus

on

this unrivalled human achievement called sci-

ence

and try to

understand

why it is so

incomparably

informative.1

The

scientific

method

is the

process

by

which scientists, collectively

and

over time, endeavour

to

construct

an

accurate (i.e., reliable, consis-

tent,

and

nonarbitrary) representation

of the

world.

It is

simply

the

gold

standard

for

knowledge.

It and it

alone

has put

planes

in the

air, bridged

giant

valleys, prolonged

life

expectancy (and

is

still

doing so),

and

1

Some

references

I

have found

useful

include Robyn

M.

Dawes,

Rational

Choice

in an

Uncertain World (New York: Harcourt Brace

Jovanovich,

1988);

Julian

Meltzoff,

Critical

Thinking

about

Research

—

Psychology

and

Related

fields

(Washington,

DC:

American

Psychological

Association, 1998);

Jeffrey

Katzer,

Kenneth

H.

Cook,

&

Wayne

W.

Crouch,

Evaluating Information:

A

Guide

for

Users

of

Social Science

Research,

2d ed.

(New York:

Random

House,

1982):

"Much

information reported

by

scientists, published

in

reputable

journals,

and

used

by

students, practicing

professionals,

and the

general public

is

mislead-

ing. Some

of it is

just

plain wrong.

The

purpose

of

this

book

is to

help

you

detect such

misinformation";

Fred Wilson,

The

Logic

and

Methodology

of

Science

and

Pseudoscience

(Toronto: Canadian Scholars' Press, 2000); Stephen

S.

Carey,

A

Beginner's Guide

to

Scien-

tific

Method,

2d ed.

(Belmont,

CA:

Wadsworth

Publishing Company, 1997);

and

Arthur

Strahler,

Understanding Science:

An

Introduction

to

Concepts

and

Issues

(Buffalo,

NY:

Prometheus

Books, 1992).

[79]

FOUR: SCIENCE: SOME

BASIC

CONCEPTS

allowed

us to

understand phenomena

from

the

closest point

at

hand

to

the

farthest reaches

of the

universe.

The

fact

that

it

comes with risks

and

dangers does nothing

to

advance

the

cause

of

competing alleged ways

of

"knowing."

The

scientific

method

is

simply

a set of

procedures

—

logical

and

demonstrably

effective

— for

testing

the

validity

of

empirical claims.

"Science"

is a

process,

not a

product.

It

primarily denotes

a

continuous

process whose basic purposes

are to

make phenomena recognizable

and

to

predict outcomes,

and

whose fundamental activities comprise

observing

and

describing phenomena

and

developing general conclu-

sions about them;

integrating

new

data

with organized observations

that

have been con-

firmed;

formulating

testable hypotheses based

on the

results

of

such integra-

tion;

testing such hypotheses under controlled, repeatable conditions;

observing

the

results

of

such testing, recording them unambiguously,

and

interpreting them logically

and

clearly;

and

actively

seeking criticism

from

fellow

participants

in the

endeavour

called

"science."

In

a

leading work

on

scientific

evidence,2

the

authors state:

Science

is

neither mechanical

nor

magical.

It is a

process

of

drawing

infer-

ences

from

evidence.

The

evidence

for

those inferences

is

generated

by

research

which necessarily employs

a

selection

of

research methods.

A

finding

is

only

as

good

as the

methods used

to

find

it.

There

is no one

best

way

to

study

a

phenomenon

of

interest. Each methodological choice

involves

tradeoffs.

The

issue, always,

is

whether

the

methodology

of the

research

is

appropriate

for the

questions posed

by the

study,

and

whether

the

conclusions drawn

are

justifiable

in

light

of the

data collected

and

everything

about

the

methods

by

which those data were generated.

The

choices

of

methods require

careful

thought, both

by

researchers

and

con-

sumers

of the

research.3

2

David

L.

Faigman, David

H.

Kaye, Michael

J.

Saks,

&

Joseph Sanders,

Modern

Scientific

Evidence,

2

vols.

(St. Paul,

MN:

West

Publishing,

1997).

3

Ibid.,

vol.

1, c. 2 at 80. The

entire section

from

47 to 82

"constitutes

a

primer

on

scientific

method."

[80]

EXPERT

EVIDENCE

IN

CRIMINAL

LAW

If

the

tests

or

experiments bear

out the

hypothesis,

it may

come

to be

regarded

as a

theory

or law of

nature.

If the

experiments

do not

bear

out

the

hypothesis,

it

must

be

rejected

or

modified.

A

classic

example

of the

scientific

method's

defeat

of

authoritative

wrongheadedness

is the

"childbed fever" chapter

in

nineteenth-century

medicine.

Ignaz

Semmelweis,

a

young Hungarian doctor working

in the

obstetrical ward

of

Vienna General

Hospital

in the

late

1840s,

was

dis-

mayed

at the

high death rate among

his

patients.

He had

noticed that

nearly

20

percent

of the

women under

his and his

colleagues' care

in

Division

I of the

ward (i.e.,

the

division attended

by

physicians

and

male

medical

students) died shortly

after

childbirth.

This

phenomenon

had

come

to be

known

as

"childbed fever." Alarmingly, Semmelweis

noted

that

this death rate

was

four

to

five

times greater than

that

in

Division

II

of

the

ward (i.e.,

the

division attended

by

female

midwifery

students).

On one

particular occasion, Semmelweis

and

some

of his

colleagues

were

in the

autopsy room performing autopsies

as

they

often

did

between

deliveries.

They were discussing their concerns about death rates from

childbed

fever.

One of

Semmelweis's friends

was

distracted

by the

conver-

sation,

and he

punctured

his

finger

with

the

scalpel. Days later, Semmel-

weis's

friend

became quite sick, showing symptoms

not

unlike those

of

childbed

fever.

This

observation, however tragic, suggested

a

link between

the

per-

forming

of

autopsies

and the

"childbed fever" being

suffered

by

women

being seen

by

medical

staff

immediately

after

the

autopsies.

The

next

step

was to

"test"

this hypothesis, however vague

and

apparently ill-

formed.

Semmelweis instituted

a

strict hand-washing policy among

his

male

medical students

and

physician colleagues

in

Division

I of the

ward.

Everyone

was

required

to

wash

his

hands with chlorinated lime water

before

attending patients. Mortality rates immediately dropped

from

18.3

percent

to 1.3

percent and,

in

fact,

not a

single woman died

from

child-

birth between March

and

August

of

1848

in

Semmelweis's division.

Thus,

even before medical science

had

reached

the

stage where

a

theo-

ry

or

explanation

was

possible, because

the

discovery

of

germs

and

other

invisible

disease carriers

still

lay in the

future,

observation leading

to

hypothesis leading

to

systematic testing could achieve remarkable results.

This

obvious lesson

from

the

"childbed fever" example

is

important,

but

even

more important

is a

second lesson that both demonstrates

the

importance

of

science

and

also

the

hurdles

it

must overcome.

Despite

the

dramatic reduction

in the

mortality rate

in

Semmelweis's

ward,

his

colleagues

and the

greater medical community greeted

his

[81]