What are 'Valid and Sound?' - Gentleman Thinker

Are your arguments valid? Are they sound? What does those terms even mean?

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[TheRoopDhillon]

When he says "giraffes aren't purple dear boy" >> lmaoo

[Magistrate_of_the_Elder]

My Phil 100 teacher linked this. Surprised to see it's Philosophy Tube, like my favourite youtube channel.

[agiar]

I found it a fun exercise to come up with an example that... (ahem) _invalidated_ the error that you made in the previous version of this video.
P1: All grapes are purple.
P2: The fruit in my hand is a grape.
C: The fruit in my hand is purple.

The logic is valid, as the conclusion necessarily follows from the premises, but the argument is not sound, _even though I am holding a purple grape in my hand, _ because not _all_ grapes are purple! The first premise is false, so even though all other premises are true, the conclusion is true, and the whole argument is valid, is cannot be _sound_ because not _all_ of the premises are true! :)

[avidreader]

i didn't realize this until now, but i needed this in my life. Subscribed!

[Curtis]

Awesome, I got a name-drop and you even pronounced my username right with the "double-o"!

[michaelkrhovjak]

The “All men are created equal” example is an equivocation fallacy. Because there taking the word “man” and implying it in two different ways.

[ComradeFurious]

If Soundness = Validity + True Premises, why would you say "valid and sound"? Isn't that redundant? Since soundness implies validity.

[jonahdunch]

Could you do one on deductive vs. inductive reasoning?

[Fiddling_while_Rome_burns]

1. Deductive reasoning is bollocks
2. This argument is deductive reasoning
3.

[hennyzhi]

Most arguments are actually valid, but few are sound. You can even have a true conclusion with no premises stated. You'd never convince anyone, but a possibility is still a possibility.

[malteeaser]

Isn't an argument just an implication with a conjunction as the antecedent?

P => Q
P

Therefore, Q

=

((P => Q) ^ P) => Q

And it is a valid argument if it is a tautology?

[ShadowZZZ]

I would interpret 'sound' more of something that upon hearing it makes intuitive sense. 'valid' is however more sophisticated than that, it takes more checking

[Rasenchidori]

Lmao I have three times bcuz your voice, I love it XD

[waytoobiased]

What are ‘Valid and Sound?’

Abby’s gender and her logical pathways.

[thegreatmosot]

can anything be actually be sound? for example, it can be argued that some people might see giraffes as purple due to having colour blindness, therefore the given example can be considered sound to a certain extent. I mean if we remain sceptical then nothing would be sound arguments just valid. When do we establish that the given premises are true and not just coincidence?

[guilhermeadan]

fast and great ! my test is in 20 min and this really helped lol

[rraacchh]

Sending this to some of my religious fundamentalist relatives. I can't even count the number of times I've heard them argue that complex beings could not have evolved and humans are complex beings, therefore God did it. Hopefully explaining to them why this argument is neither valid, nor sound, will at least get them to stop saying this and then getting all smug like they just simultaneously disproved evolution and proved god. All you proved is that logic is not your strong suit.

[mostexcellentlordship]

The giraffe argument is valid, but not sound.

Truth of the premises is related to soundness, not validity.

Invalid would be:

All giraffes are purple
Gerald is giraffe
Therefore, Gerald is a frog

[mjrdd]

How can I know the premise "if p then q" and "if q then r" sound? Homework is so hard :(

[TheMorning_Son]

The all valid arguments are consistent and not necessarily true?