Phil 148. Chapter 3. What makes an argument good?. It is often taken to be the case that an argument is good if it is persuasive, that is, if people are inclined to accept it.
(VALID) If both premises were true, then the conclusion would have to be true as well.
(UNSOUND) The second premise is false.
(VALID) If the premises were true, then the conclusion would have to be.
(UNSOUND) At least premise 2 is false.
Here is a valid argument but the premises could stand some justification. Here you would expect separate arguments to be set forth.
But of course this arguments premises as well should be justified. At some point one might reach statements that are widely acceptable on their own.