The relativist fallacy, also known as the subjectivist fallacy, is claiming that something is true for one person but not true for someone else, when in fact that thing is an objective fact. The fallacy rests on the law of noncontradiction. The fallacy applies only to objective facts, or what are alleged to be objective facts, rather than to facts about personal tastes or subjective experiences, and only to facts regarded in the same sense and at the same time.
A false dilemma, also referred to as false dichotomy, is an informal fallacy based on a premise that erroneously limits what options are available. The source of the fallacy lies not in an invalid form of inference but in a false premise. This premise has the form of a disjunctive claim: it asserts that one among a number of alternatives must be true. This disjunction is problematic because it oversimplifies the choice by excluding viable alternatives, presenting the viewer with only two absolute choices when in fact, there could be many.
A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation. It is a statement that, despite apparently valid reasoning from true premises, leads to a seemingly self-contradictory or a logically unacceptable conclusion. A paradox usually involves contradictory-yet-interrelated elements that exist simultaneously and persist over time. They result in "persistent contradiction between interdependent elements" leading to a lasting "unity of opposites".
In classical rhetoric and logic, begging the question or assuming the conclusion is an informal fallacy that occurs when an argument's premises assume the truth of the conclusion, instead of supporting it.
A fallacy is the use of invalid or otherwise faulty reasoning, or "wrong moves," in the construction of an argument, which may appear stronger than it really is if the fallacy is not spotted. The term was in the Western intellectual tradition introduced in the Aristotelian De Sophisticis Elenchis.
A faulty generalization is an informal fallacy wherein a conclusion is drawn about all or many instances of a phenomenon on the basis of one or a few instances of that phenomenon. It is similar to a proof by example in mathematics. It is an example of jumping to conclusions. For example, one may generalize about all people or all members of a group, based on what one knows about just one or a few people:
The fallacy of suppressed correlative is a type of argument that tries to redefine a correlative so that one alternative encompasses the other, i.e. making one alternative impossible. This has also been known as the fallacy of lost contrast and the fallacy of the suppressed relative.
In philosophy, correlative-based fallacies are informal fallacies based on correlative conjunctions.
The Texas sharpshooter fallacy is an informal fallacy which is committed when differences in data are ignored, but similarities are overemphasized. From this reasoning, a false conclusion is inferred. This fallacy is the philosophical or rhetorical application of the multiple comparisons problem and apophenia. It is related to the clustering illusion, which is the tendency in human cognition to interpret patterns where none actually exist.
A complex question, trick question, multiple question, fallacy of presupposition, or plurium interrogationum is a question that has a presupposition that is complex. The presupposition is a proposition that is presumed to be acceptable to the respondent when the question is asked. The respondent becomes committed to this proposition when they give any direct answer. When a presupposition includes an admission of wrongdoing, it is called a "loaded question" and is a form of entrapment in legal trials or debates. The presupposition is called "complex" if it is a conjunctive proposition, a disjunctive proposition, or a conditional proposition. It could also be another type of proposition that contains some logical connective in a way that makes it have several parts that are component propositions.
An appeal to probability is the logical fallacy of taking something for granted because it would probably be the case. Inductive arguments lack deductive validity and must therefore be asserted or denied in the premises. A mere possibility does not correlate with a probability, and a mere probability does not correlate to a certainty, nor is just any probability that something happened or will happen sufficient to qualify as knowing that it did or will happen.
In linguistics, a pro-form is a type of function word or expression that stands in for another word, phrase, clause or sentence where the meaning is recoverable from the context. They are used either to avoid repetitive expressions or in quantification.
Informal fallacies are a type of incorrect argument in natural language. The source of the error is not just due to the form of the argument, as is the case for formal fallacies, but can also be due to their content and context. Fallacies, despite being incorrect, usually appear to be correct and thereby can seduce people into accepting and using them. These misleading appearances are often connected to various aspects of natural language, such as ambiguous or vague expressions, or the assumption of implicit premises instead of making them explicit.
In philosophical logic, the masked-man fallacy is committed when one makes an illicit use of Leibniz's law in an argument. Leibniz's law states that if A and B are the same object, then A and B are indiscernible. By modus tollens, this means that if one object has a certain property, while another object does not have the same property, the two objects cannot be identical. The fallacy is "epistemic" because it posits an immediate identity between a subject's knowledge of an object with the object itself, failing to recognize that Leibniz's Law is not capable of accounting for intensional contexts.
In philosophy, a formal fallacy, deductive fallacy, logical fallacy or non sequitur is a pattern of reasoning rendered invalid by a flaw in its logical structure that can neatly be expressed in a standard logic system, for example propositional logic. It is defined as a deductive argument that is invalid. The argument itself could have true premises, but still have a false conclusion. Thus, a formal fallacy is a fallacy where deduction goes wrong, and is no longer a logical process. This may not affect the truth of the conclusion, since validity and truth are separate in formal logic.
Philosophy of logic is the area of philosophy that studies the scope and nature of logic. It investigates the philosophical problems raised by logic, such as the presuppositions often implicitly at work in theories of logic and in their application. This involves questions about how logic is to be defined and how different logical systems relate to each other. It includes the study of the nature of the fundamental concepts used by logic and the relation of logic to other disciplines. According to a common characterization, philosophical logic is the part of the philosophy of logic that studies the application of logical methods to philosophical problems, often in the form of extended logical systems like modal logic. But other theorists draw the distinction between the philosophy of logic and philosophical logic differently or not at all. Metalogic is closely related to the philosophy of logic as the discipline investigating the properties of formal logical systems, like consistency and completeness.
Slothful induction, also called appeal to coincidence, is a fallacy in which an inductive argument is denied its proper conclusion, despite strong evidence for inference. An example of slothful induction might be that of a careless man who has had twelve accidents in the last six months and it is strongly evident that it was due to his negligence or rashness, yet keeps insisting that it is just a coincidence and not his fault. Its logical form is: evidence suggests X results in Y, yet the person in question insists Y was caused by something else.
Appeal to accomplishment is a genetic fallacy wherein Person A challenges a thesis put forward by Person B because Person B has not accomplished similar feats or accomplished as many feats as Person C or Person A.
