SOLUTION: I'm trying to figure out if this is a valid or invalid argument. I have been trying to use a truth table to prove , but am having a hard time. the argument is: if something is a

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Question 540541: I'm trying to figure out if this is a valid or invalid argument. I have been trying to use a truth table to prove , but am having a hard time.
the argument is:
if something is a bug then it is ugly
spiders are ugly
conclusion spiders are a bug
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
If something is a bug then it is ugly. - Draw a large oval or circle and label it ugly (just outside its edge).
You know that the set of the bugs is included in the set of the ugly things. So draw a smaller circle or oval totally inside the previous one and write bugs inside that smaller circle.
spiders are ugly - You would also draw a small circle for the set of the spiders inside the large ugly circle, but it could be totally inside the bugs circle, totally outside the bugs circle, or partially overlapping it. We just don't know. So your conclusion is not valid. You cannot conclude anything from the information given.
ANOTHER WAY:
What if the argument said pit bulls are ugly instead of spiders are ugly? Would you conclude that pit bulls are bugs?
ON THE OTHER HAND
If the argument instead said that spiders are bugs, you would know to draw the spiders set circle inside the bugs circle, and seeing that it is also inside the ugly circle, you could conclude that spiders are ugly.