If you had to memorize the following num-
ber sequence you could probably do it in a
few minutes and with practice retain it:
3 8 6 1 4 0 2 9 7 5
But if we put the numbers in logical order, it’s a snap:
1 2 3 4 5 6 7 8 9 0
What we write must logically fit together.
1 With a logical order,
we can both extend the logic,
11 12 13 14 15 16 17 18 19 20,
or even extrapolate it
2 4 6 8 10 12 14 16 18 20,
with no problem following and remembering it.
Reasons and Reasoning
The above presentation of logic was representative, using num-
bers. However, in legal logic, i.e. argument, we persuade with
both reasons and reasoning.
Our reasons begin and inform the process. These are the facts and
parties that push the lawsuit forward. In logical terminology, they
form the premises to get us to a conclusion.
Our reasoning, though, is the process to reach the conclusion.
This means taking the facts, motivations and lawsuit and applying
law to it. Legal reasoning starts with a known premise—e.g.,
“Think Like A Lawyer”
ARIZONA ATTORNEY JANUARY 2014 18
statute, rule, case—to an unknown conclusion. Logicians use the
terms “premise” and “ergo/therefore” to get to a “conclusion.”
We lawyers instead say “points” or “issues” to get “relief.” Either
way, it’s a syllogism.
A motion or brief is just an expanded syllogism.
The Legal Syllogism
Syllogisms were the main tool of philosophy for Aristotle and
later Thomas Aquinas (who synthesized Aristotle for Christina
Europe). The classic example of a syllogism is:
Major Premise = All Men are mortal.
Minor Premise = Aristotle is a man.
Conclusion (“Ergo” or “thus”) = Aristotle is mortal.
The syllogism as the basic tool of legal reasoning is also clear. In
Miranda v. Arizona, for instance, Chief Justice Earl Warren artic-
ulated the following:
“[T]he Fifth Amendment privilege is available outside of crimi-
nal court proceedings … to protect persons … from being com-
pelled to incriminate themselves … in-custody interrogation of
persons … contains inherently compelling pressures … to com-
pel him to speak …. [T]o combat these pressures … the accused
must be adequately and effectively appraised of his rights.”
Breaking this down syllogistically yields the following:
Major Premise = The Fifth Amendment protects against
Minor Premise = Police interrogation inherently compels
2. Clarence Darrow making a
“The rules of logic are invaluable
to courts, and the fallacies of an
by casting it
in the form of
JURISPRUDENCE 200 (1972),
quoted in BRYAN A. GARNER, THE
WINNING BRIEF: 100 TIPS FOR
PERSUASIVE BRIEFING IN TRIAL
AND APPELLATE COURTS 86 (2d
St. Thomas Aquinas
1. Our word text, as in textbook, comes from the Latin textus,
to weave, construct or compose and is also the origin of the
English word textile as well as context, pretext, and subtext.
From subtext also comes subtle.
3. GARNER, WINNING BRIEF at 86
(“Every good legal argument is
cast in the form of a syllogism.”). 1. Miranda v. Arizona, 384 U.S. 436, 467 (1966).