# Name of the "We change something but everything else will remain unaffected" fallacy **URL:** \ **Category:** Factual Questions\ **Created:** [May 14, 2018, 3:42pm UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140 "2018-05-14T15:42:01Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [May 14, 2018, 3:42pm UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/1 "2018-05-14T15:42:01Z")
Trying to find an established/formal term for this fallacy: \*“Right now we sell blue jeans for $20 a pair, and we sell 10,000 pairs a month, earning $200,000 a month. So if we increase our blue-jean prices to $100 a pair, then we will earn $1 million a month.” \* The flaw being that if the price of blue jeans rises, customers will buy fewer of them, and so you won’t have simply quintupled your revenue by quintupling the product price. Maybe…“inelastic behavior fallacy?” ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [May 14, 2018, 3:52pm UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/2 "2018-05-14T15:52:40Z")
[The Law of Unexpected Consequences](https://en.wikipedia.org/wiki/Unintended_consequences) ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [May 14, 2018, 3:53pm UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/3 "2018-05-14T15:53:49Z")
I think of it as the Corporate Merger Press Release fantasy. The name of the company changes, but of course price hikes and mass layoffs are not on the horizon. ---
**Author:** ![griffin1977](https://avatars.discourse-cdn.com/v4/letter/g/977dab/32.png) [@griffin1977](https://boards.straightdope.com/u/griffin1977)\ **Post date:** [May 14, 2018, 5:39pm UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/4 "2018-05-14T17:39:03Z")
I think this is the linear fallacy. Or linear behaviour fallacy. The fallacy is that the revenue generated by selling jeans is simply a linear relationship: revenue = price \* constant Whereas it is a much more complicated equation, with many variables. ---
**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\ **Post date:** [May 15, 2018, 4:46am UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/5 "2018-05-15T04:46:59Z")
When presented as an assumption, it’s sometimes called _[ceteris paribus](https://en.wikipedia.org/wiki/Ceteris_paribus)_, or “All else being equal.” ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [May 15, 2018, 4:53am UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/6 "2018-05-15T04:53:46Z")
Also is there something like an extrapolation fallacy? e.g. “We doubled our sales of foot spas last month. So, if we plot a graph, we see everyone on earth will own 10 foot spas by the end of next year!” ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [May 15, 2018, 5:14am UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/7 "2018-05-15T05:14:10Z")
> [@Measure\_for\_Measure](#): > > When presented as an assumption, it’s sometimes called _[ceteris paribus](https://en.wikipedia.org/wiki/Ceteris_paribus)_, or “All else being equal.” The opposite of which is ‘mutatis mutandis’. ---
**Author:** ![DavidwithanR](https://avatars.discourse-cdn.com/v4/letter/d/3bc359/32.png) [@DavidwithanR](https://boards.straightdope.com/u/DavidwithanR)\ **Post date:** [May 15, 2018, 5:20am UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/8 "2018-05-15T05:20:00Z")
> [@Mijin](#): > > Also is there something like an extrapolation fallacy? > e.g. “We doubled our sales of foot spas last month. So, if we plot a graph, we see everyone on earth will own 10 foot spas by the end of next year!” It takes a lot of footspa to make a prediction like that. 🙂 ---
**Author:** ![puddleglum](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/puddleglum/32/137_2.png) [@puddleglum](https://boards.straightdope.com/u/puddleglum)\ **Post date:** [May 15, 2018, 2:54pm UTC](https://boards.straightdope.com/t/name-of-the-we-change-something-but-everything-else-will-remain-unaffected-fallacy/814140/9 "2018-05-15T14:54:59Z")
In economics it is called the Lucas critique.