Fallacy of division

Fallacy of division

A fallacy of division occurs when one reasons logically that something true of a thing must also be true of all or some of its parts.

An example:

  1. A Boeing 747 can fly unaided across the ocean.
  2. A Boeing 747 has jet engines.
  3. Therefore, one of its jet engines can fly unaided across the ocean.

The converse of this fallacy is called fallacy of composition, which arises when one fallaciously attributes a property of some part of a thing to the thing as a whole. Both fallacies were addressed by Aristotle in Sophistical Refutations.

Another example:

  1. Functioning brains think.
  2. Functioning brains are nothing but the neurons that they are composed of.
  3. If functioning brains think, then the individual neurons in them think.
  4. Individual neurons do not think.
  5. Functioning brains do not think. (From 3 & 4)
  6. Functioning brains think and functioning brains do not think. (From 1 & 5)

Since the premises entail a contradiction (6), at least one of the premises must be false. We may diagnose the problem as located in premise 3, which quite plausibly commits the fallacy of division.

An application: Famously and controversially, in the philosophy of the Greek Anaxagoras (at least as it is discussed by the Roman Atomist Lucretius), it was assumed that the atoms constituting a substance must themselves have the salient observed properties of that substance: so atoms of water would be wet, atoms of iron would be hard, atoms of wool would be soft, etc. This doctrine is called homeomeria, and it plainly depends on the fallacy of division.

If a system as a whole has some property that none of its constituents has (or perhaps, it has it but not as a result of some constituent having that property), this is sometimes called an emergent property of the system.

See also

External links

v · d · eInformal fallacies
Correlative-based fallacies
Deductive fallacies
Inductive fallacies
Vagueness and ambiguity
Equivocation
Questionable cause
List of fallacies · Other types of fallacy

Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • fallacy of division — a fallacy in which a term taken collectively is used as if taken distributively * * * fallacy of division (logic) The fallacy of assuming that the part or individual partakes of the characteristic of the whole or group • • • Main Entry: ↑division …   Useful english dictionary

  • Fallacy of composition — The fallacy of composition arises when one infers that something is true of the whole from the fact that it is true of some part of the whole (or even of every proper part). For example: This fragment of metal cannot be broken with a hammer,… …   Wikipedia

  • Fallacy of distribution — A fallacy of distribution is a logical fallacy occurring when an argument assumes there is no difference between a term in the distributive (referring to every member of a class) and collective (referring to the class itself as a whole)… …   Wikipedia

  • Fallacy — In logic and rhetoric, a fallacy is usually incorrect argumentation in reasoning resulting in a misconception or presumption. By accident or design, fallacies may exploit emotional triggers in the listener or interlocutor (appeal to emotion), or… …   Wikipedia

  • fallacy — /fal euh see/, n., pl. fallacies. 1. a deceptive, misleading, or false notion, belief, etc.: That the world is flat was at one time a popular fallacy. 2. a misleading or unsound argument. 3. deceptive, misleading, or false nature; erroneousness.… …   Universalium

  • Fallacy of quoting out of context — The practice of quoting out of context, sometimes referred to as contextomy or quote mining , is a logical fallacy and a type of false attribution in which a passage is removed from its surrounding matter in such a way as to distort its intended… …   Wikipedia

  • Fallacy of the single cause — The fallacy of the single cause, also known as causal oversimplification, is a fallacy of questionable cause that occurs when it is assumed that there is a single, simple cause of an outcome when in reality it may have been caused by a number of… …   Wikipedia

  • fallacy — Any error of reasoning. Reasoning may fail in many ways, and a great variety of fallacies have been distinguished and named. The main division is into formal fallacies in which something purports to be deductively valid reasoning but is not, and… …   Philosophy dictionary

  • Division by zero — This article is about the mathematical concept. For other uses, see Division by zero (disambiguation). The function y = 1/x. As x approaches 0 from the right, y approaches infinity. As x approaches 0 from the left, y approaches negative …   Wikipedia

  • composition/division, fallacies of — The fallacy of composition is one of arguing that because something is true of members of a group or collection, it is true of the group as a whole. For example, in Utilitarianism, J. S. Mill appears to argue that since each person desires just… …   Philosophy dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”