Critical Thinking for Transformative Justice

Deductive reasoning, also deductive logic
or logical deduction or, informally, "topdown"
logic, is the process of reasoning
from one or more statements (premises) to
reach a logically certain conclusion.
Deductive Reasoning
then states that
"Socrates" must be
"mortal" because he
inherits this attribute
from
his
classification as a
"man".
Deductive reasoning links premises with
conclusions. If all premises are true, the
terms are clear, and the rules of deductive
logic are followed, then the conclusion
reached is necessarily true.
Deductive reasoning (top-down logic)
contrasts with inductive reasoning (bottomup
logic) in the following way: In deductive
reasoning, a conclusion is reached
reductively by applying general rules that
hold over the entirety of a closed domain of
discourse, narrowing the range under
consideration until only the conclusion is
left. In inductive reasoning, the conclusion is
reached by generalizing or extrapolating
from initial information. As a result,
induction can be used even in an open
domain, one where there is epistemic
uncertainty. Note, however, that the
inductive reasoning mentioned here is not
the same as induction used in mathematical
proofs – mathematical induction is actually a
form of deductive reasoning.
An example of a deductive argument:
1. All men are mortal.
2. Socrates is a man.
3. Therefore, Socrates is mortal.
The first premise states that all objects
classified as "men" have the attribute
"mortal". The second premise states that
"Socrates" is classified as a "man" – a
member of the set "men". The conclusion
The law of
detachment (also known as affirming the
antecedent and Modus ponens) is the first
form of deductive reasoning. A single
conditional statement is made, and a
hypothesis (P) is stated. The conclusion (Q)
is then deduced from the statement and the
hypothesis. The most basic form is listed
below:
1. P → Q (conditional statement)
2. P (hypothesis stated)
3. Q (conclusion deduced)
In deductive reasoning, we can conclude Q
from P by using the law of detachment.
However, if the conclusion (Q) is given
instead of the hypothesis (P) then there is no
definitive conclusion.
The following is an example of an argument
using the law of detachment in the form of
an if-then statement:
1. If an angle satisfies 90° < A < 180°,
then A is an obtuse angle.
2. A = 120°.
3. A is an obtuse angle.
Since the measurement of angle A is greater
than 90° and less than 180°, we can deduce
that A is an obtuse angle.
The law of Syllogism takes two
conditional statements and forms a
conclusion by combining the hypothesis of
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