Recent content by Skomatth

Honestrosewater, Can you recommend an intro book on semantics?

One way to resolve the tension between the formal and informal reasoning is to say that you haven't properly translated Q and R. These two sentences have equivalent meanings: 1)I have enough money to buy coffee. 2)Possibly, I could buy coffee. Since they have the same meaning, they...

I have a couple of true and false questions I'm looking at in order to review for my final next Friday (not tomorrow). First, when someone says that a function is continuous does that mean continuous on its domain or continuous at all reals? For example, tan(x) is continuous on its domain but...

I found this proof on a blog I read. Can you find what (if anything) is wrong with it? Here's a link to the whole post: http://www.analphilosopher.com/posts/1068508260.shtml"

Next semester I'm taking Intro to Physics II and Calculus II concurrently. Calc II is a co-requisite for Physics II, but in Physics I I've found that sometimes the teacher presumes knowledge not yet taught in Calc I (co-requisite for physics I). I was wondering if there were any topics in Calc...

Irving M. Copi and Carl Cohen, Intro*duction to Logic is the best to my knowledge. If you're planning to take the class sometime in the future, figure out what text your college uses and just get that. If you're looking for something cheap and easy (you can learn basic skills very quickly)...

I wouldn't trust that dumblaws.com site. For example, it says Tennessee (my homestate) has outlawed interracial marriage. But any idiot with a computer can look up the state constitution and see that that particular section has been repealed.

Judging by the context of the problem this is irrelevant.

A pulsar is a rapidly rotating neutron star that emits a radio beam the way a lighthouse emits a light beam. We receive a radio pulse for each rotation of the star. The period T of rotation is found by measuring the time between pulses. The pulsar in the Crab nebula has a period of rotation of...

Thanks I got it.

A 1000kg boat is traveling at 90km/h when its engine is shut off. The magnitude of the frictional force f between the boat and water is proportional to the speed v of the boat: f=70v where v is in meters per second and f is in Newtons. Find the time required for the boat to slow to 45 km/h...

I've only seen predicate logic that has one variable after a general term like Fx, Gy, etc. What does it mean to have several variables after a general term?

I'll take #1. Are you using relations in 2 and 3? I'll admit I never studied those on my own(taking a logic course next semester). 1| (((X&Z)&Y)v(~X>~Y)) [premise] 2| (X>Z) [premise] 3| (Z>Y) [premise] 4|| X...

1| (A>(B&C)) {Premise} 2| (B>(A&C)) {Premise} 3|| ~((AvB)>C) {Assumption} 4|| (AvB) {from 3} 5|| ~C {from 3} 6||| A {Assumption} 7||| (B&C)...

I'll have to give this one to AKG, although Honestrosewater's proof is correct. It was my impression that RAA proofs start by assuming the opposite of the conclusion. Honestrosewater's assumption is entailed by the negation of the conclusion by using only one inference rule, but since he didn't...