World PhiloMathematics & Design Society

False causation, also known as post hoc ergo propter hoc or false cause fallacy, causal fallacy or faulty causality, is a common logical fallacy that occurs when a cause-and-effect relationship is wrongly assumed without sufficient evidence to support it. This is a flawed conclusion because either such a relationship does not exist, or the evidence supporting it is insufficient. These fallacies can be particularly misleading in fields that rely heavily on empirical evidence and logical reasoning. Examples: In economics , one might observe that as ice cream sales increase, the rate of drowning deaths also increases. However, concluding that ice cream sales cause drowning would be a false cause fallacy; the actual cause is the warmer weather, which is a common factor that increases both the likelihood of people swimming and purchasing ice cream. One might observe that when interest rates fall, stock prices rise and conclude that lower interest rates cause the stock market to boom. Howeve

The fallacy of quoting out of context, also known as contextomy or quote mining, is an informal logical fallacy where a passage is removed from its surrounding matter in such a way that its intended meaning is distorted. This can be done intentionally, to mislead or persuade by deception, or unintentionally, due to misunderstanding of the passage's significance in its original context. The fallacy of quoting out of context is a pervasive issue that can distort the understanding and interpretation of information across various fields. Examples: In science , excerpts from scientific studies can be misleadingly cited to support commercial products or policies, when the complete study might not draw such definitive conclusions. In economics , this could manifest as selectively citing economic data or a statement from an economist to support a particular viewpoint, while ignoring other relevant information that would provide a more comprehensive understanding.  An economist's nuance

The fallacy of division is a logical error that involves assuming that what is true for a whole is also true for its individual parts. This type of reasoning can lead to incorrect conclusions in various fields.  Examples: In physiology , one might erroneously conclude that because the human body can resist certain temperatures, each cell can do the same, which is not necessarily the case.  In medicine , it might be assumed that if a medication works for a population, it will work for every individual within that group, disregarding personal allergies or conditions.  In pharmacy , one might think that if a compound has a specific effect, each component of that compound must have the same effect, which overlooks the complexity of chemical interactions. In dentistry , one might think that if sugar causes cavities, then every individual who consumes sugar will develop cavities, failing to consider oral hygiene and individual susceptibility. In genetics , it could be the mistaken belief tha

The fallacy of composition arises when it is assumed that what is true for individual members of a group must be true for the group as a whole.  Examples: If each component of a machine operates quietly, one might incorrectly conclude that the machine as a whole operates quietly, which may not be the case due to the interaction of parts.  In physiology , for instance, the fallacy of composition might lead one to assume that if a single cell can generate energy, then the entire organism must be brimming with energy, ignoring the complex systemic interactions that determine an organism's energetic state.  In  medicine , it could be mistakenly assumed that because a drug works for one individual, it will work for all, disregarding genetic and environmental factors that affect drug efficacy.  In  pharmacy , the fallacy might manifest in the belief that if one component of a compound is effective, the entire compound must be effective, which overlooks the role of synergistic or antagoni

The etymological fallacy occurs when an argument is made based on the assumption that the original or historical meaning of a word or phrase is necessarily similar to its actual present-day usage.  This fallacy ignores the natural development of language, where meanings shift over time due to cultural and contextual changes. This fallacy can lead to misunderstandings when terms evolve to encompass new discoveries or concepts.  Examples: The term 'atom' originally meant 'indivisible' in ancient Greek, but modern science has shown that atoms are composed of smaller particles like protons, neutrons, and electrons.  The word 'organic,' which etymologically relates to organs and living systems, but in chemistry , it refers to compounds containing carbon, regardless of their relation to life processes.  In physiology , the term 'hysteria' originally referred to a medical condition thought to be specific to women, derived from the Greek word for uterus, 'hy

The continuum fallacy, also known as the fallacy of the beard or sorites fallacy, or the bald man fallacy, is a logical fallacy where someone argues that because there is no clear line between two extremes, they are actually the same thing. The continuum fallacy is a reminder of the complexities in categorizing natural phenomena and the importance of acknowledging the spectrum of states that exist. The continuum fallacy is often encountered in everyday reasoning and scientific discussions alike.  Examples: The paradox of the heap , which questions when a heap of sand ceases to be a heap as grains are removed, illustrates how small changes can lead to significant categorical differences, challenging the notion of clear-cut boundaries.  In the debate over what constitutes a living organism . Viruses, for instance, exhibit characteristics of both living and non-living entities, leading to disputes over their classification.  In the discussion of mental health disorders , where the distinc

The Burden of Proof fallacy, also known as "Onus Probandi," is a common logical fallacy that occurs when someone makes a claim and expects others to disprove it, rather than providing evidence to support their claim. This fallacy is seen in various fields, where individuals may use this tactic to shift the responsibility of proving their argument onto others. Examples: In physiology , this might manifest as a researcher stating a new therapy is effective without presenting data, expecting skeptics to prove its ineffectiveness.  In medicine , a doctor may assert a treatment's benefits without substantiation, placing the onus on others to show it's ineffective. Dentistry is not exempt; a new dental procedure may be touted as superior without comparative studies, and critics are asked to prove it isn't. In pharmacy , a claim that a drug is safe without clinical trial results is another example.  Astronomy is not immune; one might claim a celestial body has specific p