Analogical reasoning involves comparing two entities or instances that share some attributes and using that comparison to draw a conclusion about another attribute. Arguments from analogy can vary in strength based on factors like the number and relevance of similarities between the primary and secondary analogues. Analogical reasoning is commonly used in legal arguments because the English common law system relies heavily on precedent from past cases. However, analogies in law can be complex due to diverse court systems and the creative reasoning of lawyers and judges.

1.  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.

2.  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.

3.  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.

4.  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.

5. ◦ 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.

6.  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.

7.  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.

8.  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.

9.  Moral Reasoning and Analogies: The Case of
Fetal Abuse

10.  Moral Reasoning and Analogies: The Case of
Fetal Abuse