Logical Reasoning

PT120 · S1 · Q12 All known living things are

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All known living things are made of the same basic kinds of matter, are carbon based, and are equipped with genetic codes.

Conclusion (So)

Human life has the same origin as all other known life.

Evidence

All life is made of the same basic kinds of matter; it's all carbon based; and it's all equipped with genetic codes.

Evaluate

We're trying to prove that human life has "the same origin" as all other life. The argument didn't provide a proving-mechanism for "same origin"; in other words, it didn't provide us with any rule that says,

If xyz is true, then same origin

So we know that the correct answer will have to be a rule like that.

It will take something we know about human life vs. all other life, and output "same origin".

Goal

We know three ways in which human life is similar to all other life, so let's look for any of these as possible answers:

both made same kind of matter → same origin both carbon cased → same origin both equipped w/ genetic codes → same origin

12.

The conclusion follows logically if which one of the following is assumed?

  1. Without the existence of other

    Unrelated to Goal

    This is not a rule that can prove "same origin", so it's functionally useless to us. We need some proving-mechanism for "same origin", like if xyz is true ? same origin On Sufficient Assumption, the correct answer combines with some piece(s) of existing evidence and allows us to derive the conclusion. We can't derive "same origin" if neither the evidence nor the answer choice use that term.

    3% picked this

  2. There are not any living

    Unrelated to Goal

    This is not a rule that can prove "same origin", so it's functionally useless to us. We need some proving-mechanism for "same origin", like if xyz is true ? same origin On Sufficient Assumption, the correct answer combines with some piece(s) of existing evidence and allows us to derive the conclusion. We can't derive "same origin" if neither the evidence nor the answer choice use that term.

    9% picked this

  3. There can never be any

    Unrelated to Goal

    This is not a rule that can prove "same origin", so it's functionally useless to us. We need some proving-mechanism for "same origin", like if xyz is true ? same origin On Sufficient Assumption, the correct answer combines with some piece(s) of existing evidence and allows us to derive the conclusion. We can't derive "same origin" if neither the evidence nor the answer choice use that term.

    6% picked this

  4. Many yet-to-be-discovered types of living

    Unrelated to Goal

    This is not a rule that can prove "same origin", so it's functionally useless to us. We need some proving-mechanism for "same origin", like if xyz is true ? same origin On Sufficient Assumption, the correct answer combines with some piece(s) of existing evidence and allows us to derive the conclusion. We can't derive "same origin" if neither the evidence nor the answer choice use that term.

    1% picked this

  5. Correct

    Any two living things made

    Why this is right

    Can it really be this easy? They're only giving us one answer that has the Conclusion's wording in it? Yes, it can! That's the joy of Sufficient Assumption. The correct answer combines with stuff we know from the evidence to allow us to derive the conclusion. If we're concluding something about "Z", then either the premise or the correct answer needs to mention Z. So if the premises never mentioned Z, then the correct answer absolutely has to. This gives us a proving-mechanism for "same origin": If two living things are then they have made of the same basic ? the same origin kinds of matter We know that human life is made of the same basic kinds of matter as all other known life (since all known living things are made of the same basic kinds of matter). According to this rule, if two things are made of the same basic matter, then they have the same origin. So this proves that human life has the same origin as all other life.

    Skill tested: Sufficient Assumption · how this choice captures the argument's function is the move to repeat next time.

    81% picked this

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