Deductive Logic [Part 3]

Deductive Reasoning vs. Inductive Reasoning in a Nutshell
Deductive reasoning: the result of a justified theory and legitimate conclusion
Inductive reasoning: the result of a justified theory and a likely (50% or above) conclusion

Train Your Brain
The frontal lobes of your cerebral cortex allow you to think logically. Exercise them with brain puzzles like Sudokus or logic grid puzzles.

How to Find Faults in a Statement
1. research to find any contradicting information to the statement
2. is the supporting evidence authenticated or from a respected source?
3. how updated is the information?
4. there is often more than one possibility in a situation -- evaluate others.
5. Ask yourself reflective questions to test the strength of the argument

Reflective Questions 
- What information does this statement rely upon?
- What is the main idea in the statement?
- How could you prove this statement to be incorrect?

Warnings
Consider the outcome of your actions.
As always, remember that context is key.
Practice creative thinking.
Reflect upon your work.
Deductive reasoning functions best with the support of additional techniques (creative thoughts, reflection, background psychology knowledge)

Deductive Reasoning [Part 2]

Note: The following article may be considered subjective. Read with consideration. 

Pieces of a Puzzle

Figure I

     Our last post was the introduction to our deduction notes. Perhaps it hardly seems irrelevant, considering the title of our blog-site. Here's the catch, though: deductive reasoning examples all involve the collection of individual pieces of information that are connected to the final assumption in the end. While we see Sherlock's mind processing in the show (Figure I), I would argue that they don't show the entire cognitive procedure -- that would be terribly complicated. 

     The following is an example of a deductive reasoning question:

Mary, Janette, and Sarah went out to eat on Saturday and Sunday. When they go out together, each of them orders either fish and chips or yorkshire pudding.

Janette has yorkshire pudding if Mary has fish and chips.

Either Mary or Sarah will have fish and chips, but they won't both order it.

Janette and Sarah will not both have yorkshire pudding. 

Who ate fish and chips on Saturday and yorkshire pudding on Sunday?

Figure II

     In the questions I have reviewed, there is always an introductory statement with background information, multiple points, and a question. The first two sections are gained through the observance of the subject(s), which can be done through the application of social psychology. Noticing behavioural patterns and using body language knowledge to attribute them to an understanding of the subject is key (Figure II). This may be the importance of social psychology and the reason why this blog will start uploading posts on deduction. Another reason is because, when someone thinks Sherlock, they think of the pipe, the hat, and his deductive reasoning.

Deductive Reasoning [Part 1]

Deductive reasoning is the process of making educated assumptions from given facts (which could be taken from your social psychology knowledge). Maybe you can view it as an application of the strategies found on this blog site.

Deductive Reasoning: An Introductory Definition

1. A psychological process where the subject makes a fully-supported, accurate assumption
1. rule: the input proposition confirms the legitimacy of the output proposition through logic
1. deductive reasoning uses logic
2. deductive reasoning is not limited to logic.
2. cognitive psychology is involved in deductive reasoning
1. studies the foundations for problem-solving set of rules used in deductive reasoning
2. subjects are likely to make false assumptions when their output propositions are plausible
3. humans have 2 different systems of comprehension
1. System 1
1. automatic
2. quick-to-mind
3. near instantaneous
2. System 2
1. timely process
2. thoroughly thought-through

This is the first chapter in a reoccurring series I will upload regarding the skill of deductive reasoning. This first part addressed the main definition of the topic, but I will eventually go towards applications and tips with this technique. The speed at which these posts will be made depends upon the availability of resources and the speed at which I can access them.

Credit to:

Schechter, Joshua of Brown University. Deductive Reasoning. http://www.brown.edu/Departments/Philosophy/onlinepapers/schechter/DeductiveReasoning.pdf Accessed on 4 Mar 2012. 

Notes: 

Forthcoming in The Encyclopedia of the Mind, edited by Hal Pashler, SAGE Publishing. Editorial Board: Tim Crane, Fernanda Ferreira, Marcel Kinsbourne, and Rich Zemel.

I do not own the resources or the images used in this post. Respective links are provided either above this note or by clicking the photographs.