Valid Argument Forms 6-8

sweetsana_27

Okay so i was watching the video where JY tells us how to distinguish between Valid and Invalid argument forms and at the end he gave us a little trick to remember how to distinguish between the two and that was that:

In the valid forms, the existential statements appear first and then the universal statements.

So an example is

A some-> B-> C
-------------------
A some ->C


And in the invalid forms the universal statements appear first and then the existential statements.

So an example of this would be:

A --> B some-> C
---------------------------
A some->C

BUT, the problem is that this doesnt hold true for VALID forms 6-8 as they start with universal statements rather than existential statements. So can someone tell me a trick to remember those three.

Thanks!

joegotbored-1

Write out an example of each and name them for a memorable word in your example. Then refer to them not as valid form # whatever, but instead as valid argument ninja turtle, or valid argument Skywalker.

Or you could think of them in terms of their contrapositive form which should reverse the universal/existential statement order.