Analogical reasoning is reasoning that depends on a comparison of instances. For example:

◦ Entity A has attributes a, b, c, and z.

◦ Entity B has attributes a, b, c.

◦ Therefore, entity B probably has attribute z as well.

Analogical arguments are closely related to generalizations. In a generalization, the arguer begins with one or more instances and proceeds to draw conclusions about all members of the class.

Primary vs. Secondary Analogues: if you argue that Mariah Carey’s latest album is probably good because her two previous albums were good, the first two albums are the primary analogues, and the third, the secondary.

Principles for Evaluating Arguments from Analogy: ◦ The more relevant the similarities between

primary and secondary analogues, the stronger the argument.

◦ The greater the number of similarities between primary and secondary analogues, the stronger the argument.

◦ Differences between primary and secondary analogues are disanalogies, which can either strengthen or weaken the argument.

◦ The greater the number of similar primary analogues, the stronger the argument. Dissimilar primary analogues are counteranalogies, which weaken the argument.

◦ The more diverse the primary analogues, the stronger the argument.

◦ The more specific the conclusion, the weaker the argument.

The English ancestry of the American and Canadian legal systems means that many legal arguments are analogical in nature because the English system depends upon precedent.

However, today many of our laws are produced not by judges but by legislative bodies, codified in statute books, and periodically revised.

In law, the clarity of simple analogies is rarely found.

◦ Modes of similarity between cases are often the result of highly creative thinking by lawyers and judges and the relevance of these similarities to the proposed conclusion is often debatable.

◦ Primary analogues in law (earlier cases) do not all have equal weight. Federal courts are separate from state courts and both state and federal systems have several levels.

An essential feature of the English legal system is its dependence on precedent. However, sometimes lawyers and judges are confronted with cases lacking a clear precedent, known as cases of first impression.

◦ Attempting to resolve them by appealing to analogous instances involves even more creativity than when dealing with normal cases.

Moral Reasoning and Analogies: The Case of Fetal Abuse