Source: Andrew Terry and Des Giugni, Business and the Law, 5th Edition, 2009, Engage Learning, p133
Despite the colourful claims of some lawyers who would assert that the law possesses what amounts to a monopolv on techniques of reasoning, what they say is simply not true. The reasoning adopted by lawyers at the end of the twentieth century is the same reasoning described in detail by philosophers before the time of Christ. Any philosophical textbook effectively describes the meaning of inductive arguments and deductive arguments.
Inductive reasoning
Inductive arguments are the favourites of lawyers because they produce evidence to support the conclusion desired. Philosophically, they are not put forward as irrefutable, they are just promoted as compellin9 They proceed from the particular to the general. A typical example is the generalisation ‘all crows are black’, supported by the evidence that all the crows one has seen have been black. The difficulty is that one day a white crow may appear. The ground and the conclusion are always tentative. Sufficient repeated observation of the particular fact from which it is sought to draw the conclusion will add weight to that conclusion, but at most it remains a probable, even highly probable, conclusion. It is never certain. There always remains the possibility of an inconsistent observation arising which will challenge the conclusion.
Deductive reasoning
The deductive argument, also described by philosophers at an early date, asserts irrefutable reasons for accepting the conclusion. A common form is the syllogism:
All crows are black.
This bird is a crow.
Therefore: This bird is black
In this type of argument one proceeds from the general to the particular. A degree of precision is available in that the conclusion necessarily follows from the premises, but it is not an argumentative procedure which readilv recommends itself in the classification and reduction of legal problems. Despite its faults, legal reasoning proceeds on the inductive process. it”‘hen the question is asked, ‘why?’ then an answer must be given.
The answer derives from the faults which emerge from even a rigorous application of the deductive procedure It is foolhardy to make the ‘all’ or ‘none’ generalisation which signifies deductive reasoning. It is downright dangerous to make it in the context of dealing with the legal rights of citizens. This is not the place for an exhaustive examination of philosophical procedures suitable for adaptation by lawyers. What is important is that lawyers should be able to ascertain the real and substantial facts and issues in the problems confronting them and then discover the law most applicable. This sounds easier than it really is.
Academic and Legal English 