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A logical razor is a rational principle used to shave off possible but unrealistic or unlikely explanations for a given phenomenon. Common examples include Occam's razor and Alder's razor.

Common razors [ edit ]

Below is a short and non-comprehensive list of logical razors.

Occam's razor [ edit ]

See the main article on this topic: Occam's razor

“ ” "Pluralitas non est ponenda sine neccesitate", or plurality should not be posited without necessity. —William of Occam[1]

Occam's razor was formulated by William of Occam. In short, it states that the hypothesis that makes the fewest assumptions is the best answer for the phenomenon. Note that Occam's razor does not say that the more simple a hypothesis, the better.[1] That would let other 'explanations' gain traction.

Occam's duct tape [ edit ]

It's as if Inigo Montoya woke up in Coruscant

This is only used ironically. Also known as Occam's Krazy Glue or Occam's Stapler[2] this is pretty much the exact opposite of Occam's razor — let's see how many unnecessary and useless assumptions we can make, mmkay? It makes much more sense that an omnipotent, omniscient, omnibenevolent sentient being broke the natural laws he (or she) made in order to create the universe as we see it, right? Good thing that the being also made the world in such a way as to point away from the same entity being the creator, yeah?

Popper's Falsifiability Principle [ edit ]

See the main article on this topic: Falsifiability

“ ” In so far as a scientific statement speaks about reality, it must be falsifiable; and in so far as it is not falsifiable, it does not speak about reality. —Karl R. Popper[3]

Popper's Falsifiability Principle is an axiom suggested by philosopher Karl Popper that demands any claim be falsifiable before it be taken seriously.

Alder's razor [ edit ]

See the main article on this topic: Logical positivism

This razor was formulated by Mike Alder and is better known by its correct name, Newton's flaming laser sword. It says that whatever cannot be settled by experimentation is not worth debate.

Alder's duct tape [ edit ]

This is also only ironic. Also knowable as Alder's Krazy Glue or Alder's Stapler, or its correct name, Newton's arc welder, this is pretty much the exact opposite of Newton's flaming laser sword — let’s not expose the debate so experiments will be unnecessary or useless or conversely let’s debate the newest documented experiments just to suggest more experiments.

Crabtree's bludgeon [ edit ]

“ ” No set of mutually inconsistent observations can exist for which some human intellect cannot conceive a coherent explanation, however complicated it may be. —Presumably a guy named Crabtree[4]

Crabtree's bludgeon is an observation which serves as a foil to Occam's razor, characterising a very different cognitive process exhibited in certain kinds of people.

Hanlon's razor [ edit ]

See the main article on this topic: Hanlon's razor

“ ” Never attribute to malice that which is adequately explained by stupidity. —Robert J. Hanlon[5]

This one is easy: what's easier to believe? That the average homeopath maliciously tries to entice and seduce people into drinking water remedies? Or that the homeopath is too stupid to know that it's water dihydrogen monoxide?

Grice's razor [ edit ]

“ ” As a principle of parsimony, conversational implications are to be preferred over semantic context for linguistic explanations. —Grice, we think?[6]

Basically, when in a conversation, prefer what the speaker meant over what the sentence they spoke literally meant.

Hume's razor [ edit ]

See the main article on this topic: David Hume

Hitchens at his finest.

“ ” If the cause, assigned for any effect, be not sufficient to produce it, we must either reject that cause, or add to it such qualities as will give it a just proportion to the effect. —Hume[7]

The cause must be proportionate to the effect it produces.

Hitchens's razor [ edit ]

See the main article on this topic: Christopher Hitchens

“ ” Quod gratis asseritur, gratis negatur, or what can be asserted without , or what can be asserted without evidence can be dismissed without evidence. —Christopher Hitchens[8]

Used during the act of hitchslapping, this short-but-sweet razor asserts that the burden of proof regarding the truthfulness of a claim lies with the one who makes the claim and that if this burden is not met, the claim is unfounded and its opponents need not argue further in order to dismiss it. However, this razor itself begs the question of whether it is possible to assert anything with neither implicit nor explicit evidence.

Tarzwell's razor [ edit ]

“ ” Where there is passion the truth cannot be trusted. —James Tarzwell

The essence of this razor lends itself to the idea that high emotion leads to high bias. Both science and the justice system hold that dispassion is at the core of their intentions.

See also [ edit ]