Logic class - premise or conclusion? See description.?

Question

Hey guys I have this problem for my logic class and I understand the logic terms of "premise" and "conclusion". But in this question, I am pretty sure that "Fluffy is a duck" is the premise and "Fluffy is a bird." is the conclusion, but I can't be sure and I also don't know what the premise indicator or conclusion INDICATORS are because they don't use terms like "therefore" or "thus" etc. The closest thing to a trem like that is THEN...

Here is the question/.assignment:

I. (a) Write out the conclusion for each argument below.
(b) Write out all and only the premise and conclusion indicator words/phrases (if the argument contains any, and it may not).

2. Fluffy is a duck. If Fluffy is a bird, then Fluffy is duck; and Fluffy is a bird.

(a):

(b):

Answer 1

(a) conclusion: Fluffy is a duck

(b) there are no premise or conclusion indicator words.

Many arguments have neither premise nor conclusion indicators. For these arguments you must look for an inferential relation among the statements. The meaning of the statements should reveal the conclusion. In most arguments lacking indicator words, the first statement is the conclusion.

Let B = Fluffy is a bird
Let D = Fluffy is a duck

The second statement has the meaning, if you have "B", then you have "D", and you do have "B".

So the inference is that you also have "D"

If B, then D
B
---------------
Therefore, D

This is a common valid deductive argument form known as Modus Ponens.

Answer 2

The conclusion is "Fluffy is a duck."
The easiest way to see this is to look at which sentence "forces" the other to be true. You have two sentences to look at:
1. Fluffy is a duck.
2. If Fluffy is a bird, then Fluffy is a duck; and Fluffy is a bird.

If we assume sentence 2 to be true, then sentence 1 must be true. However, if we assume sentence 1 to be true, then sentence 2 could be false. So sentence 1 must be the conclusion (assuming the argument is supposed to be valid).

I don't think there are any indicator words in that sentence, but I'm not sure how your class defines them. If there are any, the candidates would be "If," "then," and "and."
None of those words directly tell you which is the premise and which is the conclusion (the way "therefore" would), but they're important in figuring out which is which. I don't know if that makes them indicators or not.

Answer 3

When you see a sentence "If X then Y", X is the premise, Y is the conclusion.