STAGES OF HUMAN DEVELOPMENT

1. Conception

2. Zygote (first through third day).

3. Blastocyst (second day through second week)

a. By the end of the 2nd week, implants itself in uterine wall ("nidation")

4. Embryo (third through eighth week)

a. Occasional primitive heart contractions at 2 weeks;

b. Heart pumps blood and ECG tracing looks normal by 4th to 5th week;

c. Some brain activity by the end of the 6th week;

d. Normal heart functioning after the end of the 7th week.

5. Fetus (9th week until birth)

a. develops fingernails, vocal chords, taste buds, and salivary glands and begins to urinate (3rd month)

b. "quickening" = spontaneous movement, between the 13th and 20th week (3rd, 4th or 5th month).

c. develops hair and eyelashes (5th month)

d. "viability" = fetus can survive outside the mother; occurs at approximately the 24th week.

(By convention, "fetus" is sometimes used generically to refer to all the stages of pregnancy.)

6. Infant (birth until one year)

a. Meltzoff research--rudimentary shape concepts

b. self-motivated activity

7. Child (ages 1 year to 12 years)

a. capacity to communicate

b. presence of self-concepts and self-awareness

c. reasoning (developed capacity to solve new and relatively complex problems)

d. morally responsible

THE TWO MOST COMMON POSITIONS ON THE MORALITY OF ABORTION

PRO-CHOICE = Until some relatively late stage of pregnancy [from viability to birth], the mother's right to choose takes moral priority over any rights the fetus may have.

PRO-LIFE = From conception, the fetus has a right to life that takes moral priority over any rights the mother may have, except perhaps the mother's right to life.

TWO IMPORTANT DISTINCTIONS

A. Capacities And Potentialities.

X has a CAPACITY for rational thought X is able to engage in rational thought (and presumably would do so under certain circumstances).

X has a POTENTIAL for rational thought X could, under certain circumstances, develop a capacity for rational thought.

B. Human in the Biological/Genetic Sense and in the Moral Sense (Person).

1. HUMAN (IN THE BIOLOGICAL/GENETIC SENSE) = member of the species Homo Sapiens.

2. HUMAN (IN THE MORAL SENSE) = ???

PERSON: WHERE SHOULD WE DRAW THE LINE?

I. The Difference Between A Necessary Condition For Being A Person And A Sufficient Condition For Being A Person

A. Is the Capacity for Consciousness (CC) a Necessary Condition?

Person CC

-CC -Person

B. Is the Capacity for Consciousness (CC) a Sufficient Condition?

CC Person

Mary Ann Warren's Five Criteria for Personhood:

1. consciousness

2. reasoning (developed capacity to solve new and relatively complex problems)

3. self-motivated activity

4. capacity to communicate

5. presence of self-concepts and self-awareness.

A sixth criterion: moral responsibility

Why do most writers not include moral responsibility in their list of criteria for personhood?