Formal and Informal Logic: Understanding Arguments
Understanding Logic and Arguments
Logic deals with the art of reasoning and the principles of good reasoning. Logic is the science of analysis:
- Formal logic: Analyzes the structure of arguments, focusing on syntactic aspects.
- Informal logic: Examines the correct way to argue.
Formal Logic
A general debate is usually made up of sentences: premises and conclusions. All these are proposals. Logic deals with the formula; therefore, by what standards can we distinguish what is valid and what is not? Reasoning is the logical consequence of the conclusions. A reasoning is invalid if the conclusion does not follow from the premises. It is important to separate whether a conclusion is true or not from whether the reasoning is valid or not. Formal logic analyzes the forms of reasoning, regardless of the specific topic. A valid reasoning can occur even if its conclusion is false, and an invalid reasoning can have a true conclusion. The validity of logic lies in the relationship between premises and conclusion: a valid reasoning is given when, if the premises are true, the conclusion must also be true.
Informal Logic / Argumentative Interview
Formal logic provides a great opportunity to analyze whether or not valid arguments are used in any communication process. However, it is not enough to use formally valid arguments, as the success of communication may depend on other factors. On the other hand, arguments used in everyday life are often not formally valid, but we consider them correct. These are known as acceptable inferences. Informal logic studies these arguments: what are the requirements for arguments to make sense?
In direct interviews, argumentative language games involve two or more participants sending messages to each other. These messages usually follow certain rules, and these must be respected to achieve the dialogue’s aims.
Argumentative Defects or Fallacies
Some arguments seem correct, but contain mistakes: these are fallacies. Fallacies used intentionally are called sophisms, while unintentional ones are paralogisms. It is very difficult to distinguish between them, so it is better to use the term “fallacies.” To realize fallacies, we must carefully look at the context of the dialogue and the attitude of the interlocutors. Otherwise, we may not realize the fallacies.
Types of Fallacies:
- Complex Question: Some questions have presuppositions. For example, “Have you stopped bothering my cousin?” implies that the person was bothering their cousin. Whether the answer is yes or no, the presupposition is accepted. These questions are often used as fallacies.