A fallacy is a reasoning that is not correct, but seems plausible.
A number of things can be based on incorrect reasoning or fallacy, namely:
- A false deduction,
- Or a faulty induction,
- Or an erroneous Premiss,
- or incorrect semantics,
- Or there is a wrong burden of proof where the reasoning is not verifiable.
And in all cases, the inference or conclusion is therefore incorrect.
So a good reasoning always has:
- A right premise,
- A correct conclusion or inference,
- is deductively correct or inductively correct,
- Has sound semantics
- and is verifiable.
If a reasoning does not meet at least one of these points, but is recognised by people as such, it is a fallacy.
There are many species which are divided into a number of categories.
Based on false deductive reasoning (a.o.), formal fallacies:
- Argumentum ad Ignorantiam
- Argumentum AD A
- Argumentum ex Silentio
- Non sequitur
- Retrorsum causa et effectus
- Post hoc ergo propter hoc
- Jizz Hoc ergo propter hoc
- Secundum Quid
- False dichotomy
- Confirmation of the consequence
- Random correlation
Based on incorrect premisses (a.o.), informal fallacies:
- Ad hominem
- Tu quoque
- Ad to
- Ad populum
- Ad Antiquitatem
- Ad Novitatem
- Ad Baculum
- Ad odium
- Ad Misericordiam
- Argumentum ad Superbiam
Based on incorrect semantics (a.o.), Fallacies of Confusion:
- Ad AD
- Ambiguic fallacy
Based on incorrect burden of proof (A.O.):
- Quod free Asseritur Free Negatur
Axiomatic propositions without land outside themselves (A.O.):
- Petitio Princii
Other fallacies (a.o.), problems with induction, generalization or observation:
- Ad Consequentiam
- Plurium Interrogationum
- Inclined plane
Recognition and refute of fallacies
One way to recognise fallacies as such is with a Reductio ad absurdum, which is a form of an indirect evidence, which itself resembles a fallacy, but that is not. The Reductio ad absurdum has been widely used in the old Roman legal profession.A modern example of an indirect proof is a stop problem, which is widely used in computer science (discovered by Alan Turing in 1936).
Other ways to refute fallacies are:
- An allegory,
- or satire,
- Or dialectic,
- or a syllogism.
However, an apparent refutation in itself is also a fallacy, often this is:
- An error in the method,
- or an error in the definition,
- or improper inference,
- or incorrect interpretation,
- or incorrect subject,
- or incorrect proposition.
A fallacy is therefore always both inconsistent and inconsistently.