Some of you may have noticed that I enjoy debating a good many topics online. Recently, in a fairly amicable exchange, I tried to explain carefully to a colleague the issues with their argument in terms of validity, soundness, and cogency. I was immediately accused of just throwing out “word salad,” which is sad because such tools can be SUPER helpful in navigating arguments and claims. I do hope that some of you might find this simplified explanation of these terms helpful:
The structure of an argument is VALID if and only if it would be contradictory for the conclusion to be false if all of the premises are true. There is a limited number of valid forms of argument, but I won’t bore you with that here.
An example of a valid argument:
All men are mortal.
Socrates is a man.
Therefore, Socrates is mortal.
An argument can be said to be SOUND if the premises are demonstrably true. Here is an example of an argument that IS valid but IS NOT sound as all of the premises are NOT true:
All birds can fly.
Penguins are birds.
Therefore, penguins can fly.
An argument can be described as COGENT when an inductive argument (specific-to-general as opposed to the deductive general-to-specific) demonstrates that the conclusion is “more likely” to be true.
Most birds can fly.
Tweety is a bird.
Therefore, Tweety can probably fly.
Given that you don’t know anything more about Tweety than what is given in the premise—for instance, Tweety MAY BE a penguin—then it’s MORE LIKELY that Tweety can fly. Therefore, the example is cogent.
I hope that this helps some of my friends better navigate arguments online or at least better understand some of my comments in future exchanges.