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A little puzzle

Percipere'Chan
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Posted 03/14/04 - 03:26 PM:	#121
AKG, Thanks for the tutorial on Transitive / Intransitive. Seems kinda like reflexive actions (which has been mentioned previously). I think I may go back one more time to my Latin sources to see what they say about transition of action. Indeed it doesn't seem a proper use. The inability to use the "necessitates" / "is necessary for" & "suffices" / "is sufficient for" leaves a bad taste in my mouth and makes me wonder about the fundamental accuracy of our current official definition for the word but, hey. Overall, it's a great puzzle (and I'm learning a lot ) Thanks again!
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RandomPrecision
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Posted 03/26/04 - 01:35 PM:	#122
This argument has gone on for quite a while, and goes into more English and grammar than I ever cared to know about, but I thought I'd put in my two cents of an answer: cause. Oxygen is a necessary condition for fire Oxygen causes fire Light is a necessary condition for photosynthesis Light causes photosynthesis In both examples, it takes other things to cause the result as well, but I don't think "cause" implies that the antecedent is the only possible antecedent. By the way, I tried to cheat by doing a Google search for '"is a necessary condition for" "word that means"', and the site that came up on top was this thread. None of the sites below this one had anything relevant to the topic.

AKG
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Posted 03/28/04 - 07:07 PM:	#123
Cause doesn't work. Saying "A causes B" is equivalent to saying, "A is a sufficient condition for B," that is, if you have A, B will happen. It does NOT say that you NEED A for B to happen. Being punched causes bruises, but being punched isn't NECESSARY for getting bruises, you could walk into a wall, or something like that.
"The only reason we die... is because we accept it as an inevitability." -- Stewie "To enslave nuance to dogma is folly." -- Lord Hillyer

Nox
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Posted 03/29/04 - 11:10 AM:	#124
Liberepublicat wrote: I recently came across an interesting puzzle on another philosophy website: Name a verb -- one word -- that is intersubstitutable, salva veritate, for "is a necessary condition for." The only answer I can offer is "to precede" "A precedes B" means B cannot occur unless A has occured. Example: Life precedes death (death cannot occur unless life has occured). Even in such cases as "Stealing a car precedes having a car", we do not have a problem since stealing a car is not a necessary condition for having a car (your could buy a car). What say you? I can't think of anything else.

Liberepublicat
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Posted 03/29/04 - 11:58 AM:	#125
Nox wrote: The only answer I can offer is "to precede" "A precedes B" means B cannot occur unless A has occured. Example: Life precedes death (death cannot occur unless life has occured). Even in such cases as "Stealing a car precedes having a car", we do not have a problem since stealing a car is not a necessary condition for having a car (your could buy a car). What say you? I can't think of anything else. That's a fair candidate. I'm mulling it over.

AKG
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Posted 03/29/04 - 01:49 PM:	#126
Nox wrote: Even in such cases as "Stealing a car precedes having a car", we do not have a problem since stealing a car is not a necessary condition for having a car (your could buy a car). Precedes won't work. Let's look at the definition (Dictionary.com): *precede* v. tr. [list=1] To come, exist, or occur before in time. To come before in order or rank; surpass or outrank. To be in a position in front of; go in advance of. To preface; introduce: preceded her lecture with a funny anecdote. [/list]I think we can immediately see that 2, 3, and 4, won't work for us. Is there a problem with 1? Yes. You might have heard of the fallacy "post hoc ergo propter hoc," which basically says that although one event follows the other in time, that does not necessarily mean that the first event caused the second. "The Simpson's" is on at 5, "Seinfeld" is on at 5:30. The airing of "The Simpson's" precedes the airing of "Seinfeld," but not only is the airing of the first show not a necessary condition for the airing of the second, it is not a condition at all for the airing of the second.
"The only reason we die... is because we accept it as an inevitability." -- Stewie "To enslave nuance to dogma is folly." -- Lord Hillyer

Nox
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Posted 03/29/04 - 03:03 PM:	#127
"Is a necessary condition for" does not mean "is the cause for". Example: combustible is a necessary condition for combustion, but combustible is not the cause for combustion. Therefore the fallacy you quote is irrelevant to our situation. In your argument A is not a necessary condition for B, therefore your argument is false since the prime condition of our situation -- "is a necessary condition for", is unfulfilled. To counter my argument, you must search for an example when A "is a necessary condition for" B, and A "does not precede" B. I have proposed that: 1 - If A "is a necessary condition for" B 2 - then B is dependent on A 3 - then B cannot occur before A 4 - Therefore A "precedes" B is always true From which I deducted that "is a necessary condition for" = "precedes". You must demonstrate that: 1 - If A "precedes" B 2 - B can still occur without A having occured 4 - therefore B is not depedent on A 3 - therefore A "is a necessary condition for" B is false From which we will conclude that "is a necessary condition for" != (not equal to) "precedes". The case is a purely logical one.

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Posted 03/29/04 - 04:33 PM:	#128
Nox wrote: "Is a necessary condition for" does not mean "is the cause for". Example: combustible is a necessary condition for combustion, but combustible is not the cause for combustion. Therefore the fallacy you quote is irrelevant to our situation. No it's not. If something causes something else, it is a condition for that something else. It need not be a necessary nor sufficient condition, but saying A causes B implies that in some way A is a condition for B. You have to show that "A precedes B," implies that A is a condition for B. It is not. You would have to go even further and show that A is a necessary condition for B, but you haven't even made your way over the first hurdle. I have proposed that: 1 - If A "is a necessary condition for" B 2 - then B is dependent on A 3 - then B cannot occur before A 4 - Therefore A "precedes" B is always true From which I deducted that "is a necessary condition for" = "precedes". Well, you "deducted" incorrectly (by the way, you want to use the word "deduced" which means to come to a conclusion by deduction, rather than "deducted" which is when you take away something, e.g. a teacher deducted marks from the late assignment). Lines 1-4 are correct, but your deduction is faulty. (A is a necessary condition for B) --> (A precedes B) ... (1) Now, for your "proof" to be complete, for you to truly show that: (A is a necessary condition for B) = (A precedes B) you must show that: (A is a necessary condition for B) <--> (A precedes B) You've already showed the sufficiency in (1), but you need to show the necessity is true also, namely, show that: (A precedes B) --> (A is a necessary condition for B). As I have already shown this to be false, we can deduce that "precedes" is not the right word. As you said, the case is purely a logical one.
"The only reason we die... is because we accept it as an inevitability." -- Stewie "To enslave nuance to dogma is folly." -- Lord Hillyer

Nox
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Posted 03/29/04 - 06:47 PM:	#129
Sorry about the misuse of "deducted", and thanks for correcting me. English is my third language; I still switch terms every so often, especially when I type fast. No it's not. If something causes something else, it is a condition for that something else. It need not be a necessary nor sufficient condition, but saying A causes B implies that in some way A is a condition for B. True. But that A is a necessary condition for B doesn't imply that A will cause B. I was merely pointing to the fact that the puzzle was dealing with a necessary condition, not a cause. A necessary condition, a prerequisite isn't always a cause. Unless paper (a combustible/ a condition of combustion) will cause combustion without comburant. I have still to witness it. You have to show that "A precedes B," implies that A is a condition for B. It is not. You would have to go even further and show that A is a necessary condition for B, but you haven't even made your way over the first hurdle If A precedes (comes before) B, then B cannot happen unless A has happened. I would qualify A as a necessary condition for B, meaning you won't get B until you first get A. Unless of course you died before you were alive (A is a necessary condition for B) --> (A precedes B) ... (1) Now, for your "proof" to be complete, for you to truly show that: (A is a necessary condition for B) = (A precedes B) you must show that: (A is a necessary condition for B) <--> (A precedes B You've already showed the sufficiency in (1), but you need to show the necessity is true also, namely, show that: (A precedes B) --> (A is a necessary condition for B). In my world time goes forward, and what comes first MUST happen before what comes second. What comes second, CANNOT happen before what comes first. How about in yours? As I have already shown this to be false, we can deduce that "precedes" is not the right word. As you said, the case is purely a logical one. Can anything die if it never lived?

AKG
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Posted 03/29/04 - 07:23 PM:	#130
A lot of the stuff in this post may be confusing (I'm not even sure if what I wrote was correct) grammar stuff, so if you want you can ignore most of it. If you want to see where your argument is wrong, just focus on the stuff in blue. If you want to respond, it's probably only relevant to respond to that, however if you want to read the rest, go ahead. And if I've made any mistakes, in the rest of the stuff, point them out, because it's weird logic/grammar stuff that I may have messed up. However, I'm pretty certain that the stuff in blue is not messed up, and it should sufficiently show you that precedes will not work. Nox wrote: In my world time goes forward, and what comes first MUST happen before what comes second. What comes second, CANNOT happen before what comes first. How about in yours? 1) That's irrelevant 2) Saying "A is a necessary condition for B" says nothing about the time. In fact, if your answer depends on "time," it is wrong. A correct conditional statement should not rely on time. For example, a "bad" statement would be like this: Kicking a ball is a necessary condition for scoring a goal. The correct statement should be: Having kicked a ball is a necessary condition for having scored a goal. Look, it's simply this: if A is a necessary condition for B, then A precedes B. However, if A precedes B, we CANNOT conclude that A is a necessary condition for B. Saying A precedes B implies that it is possible that A is a necessary condition for B, but that is not true NECESSARILY. That is, saying something precedes something else is NOT EQUIVALENT to saying that something is a necessary condition for something else. (I kicked my roommate) implies that (I attacked my roommate), HOWEVER, (I attacked my roommate) DOES NOT NECESSARILY IMPLY that (I kicked my roommate). The problem with trying to say that "I kicked my roommate" is equivalent to saying "I attacked my roommate" is the same problem that you get if you try to say that "precedes" is equivalent to "is a necessary condition for." Or, here's another way of looking at it: You have shown that: IF (A is a necessary condition for B) THEN (A precedes B). However, to show the equivalency you desire to show, you must also show that: ONLY IF (A is a necessary condition for B) THEN (A precedes B), that is, (A precedes B) only if (A is a necessary condition for B). However, I have shown that this is not necessarily true, since my birthday may precede yours, however my birthday is not a necessary condition for yours, in fact, it is not a condition at all, in other words, like I said, my birthday does, in no way, cause or imply yours. And also, realize I made the above statement for simplicity, but again, the techincally correct statement would be: The occurence of my birthday is not a necessary condition for the occurence of your birthday. Basically you want two events which follow in logical order, but there should be no chronological order. Why? Because you want to be able to assign truth values to the antecedent and consequent. For example, you can't say that it is true that "kicking a ball," but you can say that it is true that "I have kicked a ball." Although kicking a ball if followed by scoring a goal, you don't want to say: If kicking a ball.... You'd want to say: If I have kicked a ball... And notice that you can't talk about the "time" of "I have kicked a ball." With "I have kicked a ball," it's a matter of true or false, not a matter of "when".
"The only reason we die... is because we accept it as an inevitability." -- Stewie "To enslave nuance to dogma is folly." -- Lord Hillyer

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