Deductive reasoning: How do I reason from premises?
Deductive reasoning, also called deductive logic, is reasoning which constructs or evaluates deductive arguments. Deductive arguments are attempts to show that a conclusion necessarily follows from a set of premises or hypotheses. A deductive argument is valid if the conclusion does follow necessarily from the premises, i.e., if the conclusion must be true provided that the premises are true. A deductive argument is sound if it is valid and its premises are true. Deductive arguments are valid or invalid, sound or unsound, but are never false nor true. Deductive reasoning is a method of gaining knowledge. An example of a deductive argument:
- All men are mortal
- Socrates is a man
- 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 states that "Socrates" must be mortal because he inherits this attribute from his classification as a man.
Inductive Fallacies: How Can inductive reasoning go wrong?
A formal fallacy is an error in logic that can be seen in the argument's form without an understanding of the argument's content.[1] All formal fallacies are specific types of non sequiturs.
- Appeal to probability: assumes that because something could happen, it is inevitable that it will happen. This is the premise on which Murphy's law is based.
- Argument from fallacy: assumes that if an argument for some conclusion is fallacious, then the conclusion itself is false.[2]
- Base rate fallacy: making a probability judgement based on conditional probabilities, without taking into account the effect of prior probabilities.[3]
- Conjunction fallacy: assumption that an outcome simultaneously satisfying multiple conditions is more probable than an outcome satisfying a single one of them.[4]
- Correlative-based fallacies
- Denying the correlative: where attempts are made at introducing alternatives where there are none.[citation needed]
- Suppressed correlative: where a correlative is redefined so that one alternative is made impossible.[citation needed]
- Fallacy of necessity: a degree of unwarranted necessity is placed in the conclusion based on the necessity of one or more of its premises.
- Homunculus fallacy: where a "middle-man" is used for explanation, this usually leads to regressive middle-man. Explanations without actually explaining the real nature of a function or a process. Instead, it explains the concept in terms of the concept itself, without first defining or explaining the original concept.
- Is–ought problem: the inappropriate inference that because something is some way or other, it ought to be that way.[5]
- Masked man fallacy (illicit substitution of identicals): the substitution of identical designators in a true statement can lead to a false one.[6]
- Naturalistic fallacy: a fallacy that claims that if something is natural, pleasant, popular, etc. then it is good or right.
- Nirvana fallacy: when solutions to problems are said not to be right because they are not perfect.
- Package-deal fallacy: consists of assuming that things often grouped together by tradition or culture must always be grouped that way.
Inductive reasoning: How do I reason from evidence?
Inductive reasoning, also known as induction or inductive logic, is a kind of reasoning that constructs or evaluates inductive arguments. The premises of an inductive logical argument indicate some degree of support (inductive probability) for the conclusion but do not entail it; that is, they suggest truth but do not ensure it.
Induction is employed, for example, in the following argument:
- Every life form we know of depends on liquid water to exist.
- All life depends on liquid water to exist.
Inductive reasoning allows for the possibility that the conclusion is false, even where all of the premises are true.[1] For example:
- All of the swans we have seen are white.
- All swans are white.
Note that this definition of inductive reasoning excludes mathematical induction, which is considered to be a form of deductive reasoning.
Though many dictionaries define inductive reasoning as reasoning that derives general principles from specific observations, this usage is outdated
Fallacies: What's faulty argument?
Viewpoints: What's the Filter?
Point of view in literature is probably the biggest single area of novel writing that aspiring writers have problems with.
More specifically, they often can't decide whether to use first person or third person point of view.
Actually, though, there is a bigger problem that most newcomers are not even aware of, and that is failing to handle point of view like a pro.
That is why this section on viewpoint is such a large one...
It begins by explaining the theory of point of view. A full understanding of viewpoint will not only help you to choose which point of view to use in your novel, it will also help you to then use that viewpoint like a master.
After all the theory, you will find articles on choosing a point of view. These look at the major viewpoints (first and third person), some less common viewpoints, as well as some other choices you will need to make.
You might already have a good idea on what viewpoint you will use, but I urge you to keep an open mind until you have read both sections...
- First, learn the theory of point of view in literature.
- This knowledge will help you make a better choice of which viewpoint to use.
- And the knowledge will help you to use your chosen viewpoint with more skill, too.
Evaluations: What's judged? (Chapter7)