So...war seems to suck.

[pholkhero]

Proving that something is never true is strictly equivalent to proving that the positive is always true.
In this case proving a spear can never beat a tank is exactly the same than proving the tank always beats the spear.

Just my 2 cents.

It's LOGICALLY IMPOSSIBLE to prove a negative b/c you'd need to check each and every spear to make sure that a spear could NEVER beat a tank

 

[Solo4114]

Whatever floats your boat, man. That's why I'm saying you can add stuff to make it optional. Everybody gets what they want that way.

 

[KillerCardinal]

It's LOGICALLY IMPOSSIBLE to prove a negative b/c you'd need to check each and every spear to make sure that a spear could NEVER beat a tank

Heh, not to be too confrontational, but lets say that I want to prove that 2*3=5 is not true(given the laws of arithmetic). This is easily proven.

Assume the laws of arithmetic. Suppose for the sake of contradiction that 2*3=5.

2*3=2+2+2 (by arithmetic)
2+2+2=6(by arithmetic)
Thus 2*3=6(by the transitivity of equality).
However, 2*3=5(by assumption).
Thus we have a contradiction, thus our assumption that 2*3=5 MUST NOT be true.

Thus we have proven a negative, i.e. 2*3 does not equal 5.

Mind you this isn't always possible, but proof by contradiction is a VERY valid logical proof technique, and can be used to prove a negative(and is done often).

Just to give you an idea where I'm coming from, I'm doing research in Automated Reasoning, and have taken MANY logic courses, so I do have a good idea what I'm talking about.

If anyone wants to discuss this, I'm more than happy to btw!

 

[Solo4114]

This woudl be the part in my philosophy classes where I would get bored and start thinking about epistomology instead.

 

[cabert]

Heh, not to be too confrontational, but lets say that I want to prove that 2*3=5 is not true(given the laws of arithmetic). This is easily proven.

Mind you this isn't always possible, but proof by contradiction is a VERY valid logical proof technique, and can be used to prove a negative(and is done often).

Just to give you an idea where I'm coming from, I'm doing research in Automated Reasoning, and have taken MANY logic courses, so I do have a good idea what I'm talking about.

If anyone wants to discuss this, I'm more than happy to btw!

logic isn't so widely spread on this forum
Thanks for the support, I had my share of logic courses too. Happy to know i'm not alone...

 

[Thomas G.]

About spears and arrows beating tanks...
Combat doesn't necessarily have to be a single confrontation. Each turn lasts a year, right? So a battle could take a couple of month. So, the spearmen hide out. Tank drives around a few weeks looking for them. Many spears are found and annihilated. But then some of them manage to creep up to the tanks in the middle of the night, and manage to kill a few guards silently (with their silent spears) and thus disabling the tank as a fighting force.
Not very likely, but not totally impossible.

After this they would of course pick up at least the sidearms of the tank crew and use in further operations, though.

Firearms totally revolutioned warfare because of their relatively low skill level needed to operate. Becoming a good archer or swordsman takes a lifetime, but in 2 days anyone can fire a rifle with much more effectiveness than most archers.

 

[KillerCardinal]

logic isn't so widely spread on this forum
Thanks for the support, I had my share of logic courses too. Happy to know i'm not alone...

Hmm, I've noticed. I generally try to stay out of it, but this time for some reason, I felt compelled to say something! Glad to know I'm not alone either .

 

[naterator]

2*3=2+2+2 (by arithmetic)
2+2+2=6(by arithmetic)
Thus 2*3=6(by the transitivity of equality).
However, 2*3=5(by assumption).
Thus we have a contradiction, thus our assumption that 2*3=5 MUST NOT be true.

Thus we have proven a negative, i.e. 2*3 does not equal 5.

yes, but you haven't proven that 2*3 CAN'T equal 5. there are infinite variables that you'd have to check. maybe if you stripped naked, covered yourself with motor oil, and ate 35 goldfish, THEN 2*3=5. arethmetic's different, anyway... very few shades of grey.

but proof by contradiction is a VERY valid logical proof technique, and can be used to prove a negative(and is done often).

those who challenge you to disprove their extraordinary claims, rather than offer proof themselves, aren't bound by logic as you and i understand it...

 

[dutchfire]

Spearman: "Look there are tanks coming, let's make a tank trap, and hide somewhere."
Tank drives into trap
Spearman walk to tank, open it up (eventually) and kill of the crew

 

[KillerCardinal]

yes, but you haven't proven that 2*3 CAN'T equal 5. there are infinite variables that you'd have to check. maybe if you stripped naked, covered yourself with motor oil, and ate 35 goldfish, THEN 2*3=5. arethmetic's different, anyway... very few shades of grey.

Okay, a better way to put it may be to say that this proves one of two things. Either the laws of arithmetic don't hold, OR 2*3 does not equal 5. However, since saying that the laws of arithmetic don't hold REALLY screws up a lot of things, I didn't feel it was necessary to say that. And if you want to start questioning things like that, you are no longer talking about whether or not a proof by contradiction is vaild, you are now talking about whether it is possible to prove ANYTHING, period.

Also, those other variables wouldn't affect this, as the ONLY assumptions that I made was that the laws of arithmetic hold. This means that it doesn't matter if you strip naked, ..., etc or not.

And anyway, my issue was with the comment:

It's LOGICALLY IMPOSSIBLE to prove a negative

Stating that something is logically impossible means that in every possible example, it is not possible. That is why I was talking about something as clear cut as arithmetic.

those who challenge you to disprove their extraordinary claims, rather than offer proof themselves, aren't bound by logic as you and i understand it...

Very true, but for them to be taken seriously, they do. Otherwise, a person can just suddenly say something that makes no sense, and it would have to be taken seriously.

I mainly wrote this so that others would understand that the statement wasn't true.