The assignments below range from presentations on readings to a term paper. Examples of some unique aspects of this class are the thought experiments on morality, and the thought questions.

Presentation and Paper

1. Presentation of lecture topic based on the readings or a topic approved by the instructor.
2. Paper on a topic approved by the instructors, due end of semester.

Participants had to make decisions on two different classes of fantasy dilemmas.

1. Trolley problems. Example:

A trolley is hurtling down the tracks. There are five innocent people on the track ahead of the trolley and they will be killed if the trolley continues going straight ahead. There is a spur of track leading off to the side. There is one innocent person on that track. The brakes of the trolley have failed and there is a switch which can be activated to cause the trolley to go to the side track. You are an innocent bystander. You can throw the switch saving the five innocent people, which will result in the death of the one innocent person on the side track. What do you do?

2. Lifeboat problems. Example:

A ship has sunk and there are six survivors on a lifeboat. Because of limits of size, the lifeboat can only support five individuals and you must decide what to do. Five of the six are normal adult human beings and the sixth is a collie dog. One individual must be thrown over to drown. What would you do?

a. Throw the dog over

b. Draw lots among the humans and throw the losing human over

c. Draw equal lots and throw the loser among all six over

Participants were presented with different varieties of these two dilemmas, varying on a number of dimensions. The dilemmas were constructed to allow the dimensions to be compared in importance with one another. The dimensions were (all examples are in reference to the trolley problem):

1. Action-Inaction: All the dilemmas were constructed to allow the participant to act (throw the switch) or avoid acting (let the trolley continue on its path) to see if this dimension was important in and of itself.

2. Numbers: The number of individuals on the tracks were varied. Example One: Five people versus one person. Example Two: Five people versus your brother.

3. Social contract: Varied the individuals' involvement in the situation. Example: Innocent bystanders on the track versus railroad employees working to repair the track.

4. Nazi: Included as a dimension to examine the effect of an abhorrent philosophical perspective. Example: Nazis on one track and innocent individuals on the other.

5. Inclusive Fitness: The degree of relatedness between the participant and the people on the track. Included biological relatives as well as friends and members of the same social group.

6. Elite: Individuals who have attained a high status in society. Example: innocent bystander on one track, famous scientist working on a cure for cancer on the other track.

7. Species: Example: One human on one track, five gorillas on the other track.

8. Endangered: Matched with species dimension, compared endangered species versus nonendangered versus humans.


  • Across two different studies, four different subject populations were compared: three different groups of U.S. psychology students and one group of Tiawanese students.
  • A number of differences were found across groups in terms of personal beliefs on issues such as abortion, birth control, capital punishment, medical experimentation, religious affiliation, etc.
  • On the moral dimensions manipulated in the fantasy dilemmas, however, there was very little difference across groups. Regardless of sample, individuals made very similar decisions. In other words, individuals favored members of their own species over other species; family (and friends) over strangers; found it more morally acceptable to let someone die than to kill; preferred to save more rather than fewer; utilized social contract information in their decisions; and condemned those who were Nazis. Elitism and indangered had no effect on decisions.
  • The overall order of importance of the dimensions was: Species, Inclusive Fitness, Action-Inaction, Numbers, and Social Contract, Elitism (Nazi and Endangered were not included in the Taiwanese sample). All of these, except Elitism, mattered in determining the outcome of the dilemmas.


  • The differences which were found on measures of personal belief were uncorrelated with responses on the fantasy dilemmas, suggesting that the nature of moral intuition lies at a deeper, more fundamental level than personal belief. The authors of these studies conclude that the universality of the response patterns on these fantasy dilemmas suggest at least a partial evolved, biological component to human morality.

Petrinovich, Lewis. (1995). Human evolution, reproduction, and morality. New York: Plenum Press.

Petrinovich, L., O'Neill, P. and Jorgensen, M. (1993). An empirical study of moral intuitions: Toward and evolutionary ethics. Journal of Personality and Social Psychology, 64, 467-478.

Questions for Discussion

1. What are the limitations of the fantasy dilemma methodology? Some possibilities for discussion include:

  • Limited participant sample (even with cross-cultural data, all are students)
  • Paper and pencil, questionnaire methodology (response bias)?
  • How much can we generalize from these responses to actual behavior (and how much does this matter)?

2. How convincing is this data in terms of addressing issues of biology and evolution? Can a sociocultural explanation account for these results?

3. How much of real-world morality can we map on to the universals proposed by the moral intuition research? Do the differing responses on questions of personal belief imply that real-world moral decisions might show greater variability than suggested by these proposed universals?

4. Are there additional types of evidence that might help illuminate the link between biology and morality?

A Modern Approach to Morality

Moral Intuition and Fantasy Dilemmas

  • The basic idea behind the modern evolutionary approach to morality in humans is that at least certain aspects of our moral beliefs and intuitions have a biological basis. In other words, the principals of evolutionary biology (for example the concept of inclusive fitness) might shed light on many of the behavioral tendencies that we consider moral.
  • Several moral issues have been addressed in the study of moral intuition, including:

1. Number – Should the number of individuals who are affected by a decision influence the nature of the recommended action? (i.e. You have the option of saving the life of 1 person or 5 people)

2. Action and omission – Is it more permissible to let someone die than to kill the person?

3. Social contracts – A number of social contracts can affect the morality of a behavioral decision, such as:

a. Whether a promise has previously been made to help one individual over another.

b. Personal rights and ownership

c. Costs and benefits to society

d. Biological associations – Do we feel a moral obligation to kin, or to members of our own species?

  • One way to explore this idea of a biological-based morality has been through the use of fantasy dilemmas, hypothetical situations aimed to assess people’s intuitions about moral decisions. For example:

You have access to a lifesaving drug. There is one individual who will die if he does not receive all of the drug. There are five other individuals each of whom only need one-fifth of the drug to survive. Who do you choose to give the drug to: the one person or the five people?