1. Why are we studying this?

Thinking never stops, Logical thought and it’s expression thereof is a fundamental part of our identity as a species.

• Logical thinking is a skill required for success across every trade and every profession, therefore improving one’s ability to think logically is almost always a good thing.  
• To be better at logical thinking it becomes important to dissect logic itself, To think about thinking, we refer to this as the study of the principles of Sound Reasoning.
• How to assemble a logical sentence

In written form, thoughts take the form of sentences, there are four kinds of sentences worth mentioning:

• Interrogative – A sentence that asks a question, for example “Who are you?” These kinds of sentences are neither true nor false.
• Imperative – A sentence issuing a command, for example “Identify yourself!” These kinds of sentences are neither true nor false.
• Exclamatory – A sentence expressing emotion , for example “Good God man!”  These kinds of sentences are neither true nor false.
• Declarative – A Sentence expressing information, for example “We are on high-alert so we have no time for funny business”  These sentences can be either true or False.

When reasoning aloud or in written form as a Declarative Sentence, the first Thought is called a Reason  (referred to as Premise) and the thought it leads to is called a Conclusion.

Logical Connectedness – When Linking Reasons with Conclusions, We use words like therefore, so, accordingly, and thus all typically, after a reason and before a conclusion:

• “I am tired, so I will sleep.”

Reasons are not always easy to distinguish, we use words like since, because, for, and given that all typically after a conclusion and before a reason.

• “I will sleep, because I am sleepy.”

Statements – are Declarative sentences which are either true or false.

Claim – is what a statement says about the state of affairs in the world, which is either true or false. The claim that a statement makes is also called a proposition.

(CogBook, Module 1.1)

• The difference between Truth, Facts, Representations & Validity.

Truth – What makes something true or false are the facts in the real world, independent of what we know about them.

Representation – is a portrayal of fact. Representations can vary in accuracy.

Fact – The specific part of a world which makes a statement true we call a fact or a state of affairs.

Accuracy – a representation is accurate if it corresponds to reality, a representation is inaccurate if it fails to correspond to reality. Accuracy can be subjective. Like a map drawn to show directions to a hotel.  

Validity – A valid argument is one where there is no possibility of the premises being true with the conclusion being false. In other words, if the premises are true, then the conclusion would have to be true.

Opinion/ Belief – A belief is an attitude towards a proposition. To believe a proposition is to hold that the proposition is true. Because the facts are what make propositions true, all beliefs are beliefs about what the facts are.

(CogBook, Module 1.x)

• What Bad Reasoning, Intellectual Vice and Virtue & Fallacies are

It is important to understand that People who engage in bad reasoning can often be

• Blind to their own bad reasoning, because an idea makes perfect sense in their own head, or because they’re part of a group of people who make the same mistake, affirm the same error, and amplify the same bad information throughout a group.(CogBook, Module 1.1, Sound Reasoning)
• Failing to engage in reasoning when they should. For instance, somebody who is constantly turned down on requests for a date from the same person may fail to reason to the conclusion, “this person does not want to date me”, even though they have a good reason to reach that conclusion.

As a result, it becomes important to identify character traits that contribute to and detract from an individual’s ability to arrive at the truth through sound reasoning.

• Intellectual Virtues are character traits or dispositions which tend to help reasoners to arrive at the truth.
• Intellectual Vice are character traits or dispositions which most often lead reasoners away from the truth rather than towards it. Intellectual vices tend to lead to problematic arguments, or fallacies.
• Fallacies are patterns of mistakes in reasoning that humans are especially inclined to make. Some Common Fallacies are the ‘Non-sequitur’ and the ‘Begging the question Fallacies’

There is no comprehensive list of mistakes one can make in reasoning, to identify bad reasoning it becomes important to study formal and informal logic.

• Informal logic is the study of general guidelines for good reasoning, rather than strict rules, and it tends to focus more on real-world examples where reasoning succeeds or fails.  (CogBook, Module 1.2)
• Formal logic is the study of abstract patterns of reasoning that meet the strictest standard for arguments, called validity, so that any argument which follows the pattern is guaranteed to have a true conclusion if its starting assumptions, or premises, are true. (CogBook, Module 1.2)