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If "not alive" => "doesn't need resources", then "needs resources" => "alive". That doesn't seem right to me.
by computerphage 9y ago
If "not alive" => "doesn't need resources", then "needs resources" => "alive". That doesn't seem right to me.
- Sophistifunk 9y agoThat's... not how logic works.
- ianterrellwt 9y agoI think that might be how logic works. The fallacy seems to be with its parent. https://en.wikipedia.org/wiki/Contraposition https://en.wikipedia.org/wiki/Contraposition
- Sophistifunk 9y ago"Alive implies needs-resources" is not the same as "needs-resources implies alive"
- dpark 9y agoOf course not. And if he'd said "alive implies needs resources", the argument would not be valid. ianterrelwt posted the article explaining this.
- andrewflnr 9y agoYou don't need to hedge. That's exactly how logic works.
- deleted 9y ago[deleted]
- ssambros 9y agoThat's exactly how logic works.
- computerphage 9y agoYes... it is. https://en.wikipedia.org/wiki/Contraposition https://en.wikipedia.org/wiki/Contraposition
- pvg 9y ago"All cats die. Socrates is dead. Therefore Socrates is a cat."
- ajnin 9y agoNo. Mirroring the parent would be : "All cats die. Socrates is immortal. Therefore Socrates is not a cat." Which is perfectly valid logic.
- pvg 9y agoI'll let Eugène Ionesco know.
- uzoodoo 9y agoMore like: "Non-living things don't move. The bus moves. Therefore, the bus is alive." This is false because there exist things that are non-living but move. Similarly, the original "not alive" => "doesn't need resources" argument is false because there exist things that are not alive that do need resources (such as buses), and so needing resources does not imply being alive.
- DiThi 9y agoThat's a deductive fallacy. Alive things need resources, but things that need resources are not necessarily alive.
- irisli 9y agocomputerphage wasn't using deduction but rather contraposition. (A -> B) => (!B -> !A). The absurdity of (!B -> !A) shows that (A -> B) is not true for all cases.
- uzoodoo 9y agoBut the premise "not alive => doesn't need resources" is false because there exist things are "not necessarily alive" that need resources. Therefore, the argument is invalid.
- computerphage 9y agoIt's not a fallacy. The truth table for implication and its contrapositive are the same. A | B | A => B | ¬B => ¬A T | T | T | T T | F | F | F F | T | T | T F | F | T | T My original point was that my parent was implicitly claiming that only living things need resources. That seemed absurd to me because of things like viruses, companies, governments, etc.
- jcoffland 9y agoI said, "do not need to compete for resources to further their existence." This is not the same as "do not need resources."