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#72676
Complete Question Explanation

Must Be True-Principle. The correct answer choice is (C).

Answer choice (A):

Answer choice (B):

Answer choice (C): This is the correct answer choice.

Answer choice (D):

Answer choice (E):


This explanation is still in progress. Please post any questions below!
 spum123
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#73166
Could someone please diagram this out, I am having a very difficult time understanding this question.
 James Finch
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#73204
Hi Spum,

This conditional principle is confusing because of the "if" part of the necessary condition, but for the purposes of this question it is just a part of the necessary condition. So, using the Unless Equation, the conditional statement is:

Empirical Theory (ET) :arrow: Conceivable Observation That Would Refute if Theory False (COWR)

and the contrapositive:

COWR :arrow: ET

To get to the correct answer choice, all that needs to be done is to find the one that matches either the conditional statement as given or its contrapositive. (C) does this by giving us:

COWRPsychoanalysis :arrow: ETPsychoanalysis

Carbon copy of the contrapositive.

Hope this clears things up!
 lathlee
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#74422
I am so sorry to ask this but can you explain through nested conditional way? Cuz I don't see answer c, can be the right answer according to how nested conditional way
 Jeremy Press
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#74467
Hi lathlee,

A nested conditional diagram would look like this:

PRE :arrow: (F :arrow: Some COR)

PRE = properly regarded as empirical
F = false
COR = conceivable observation would refute

What it means is that IF a theory is properly regarded as empirical, THEN it MUST be the case that if that theory were false, there would be some conceivable observation that would refute it.

Answer choice C applies the contrapositive of that nested conditional, so we need to think about the contrapositive of the nested conditional.

In a broad sense, to get our sufficient condition of that contrapositive, we just need a negated form of what I've diagrammed in parentheses as the original necessary condition. But what is the negation of a conditional statement? It's the possibility that the sufficient condition of that conditional occurs WITHOUT the necessary condition. So, in this case, the sufficient condition of the contrapositive would be a theory that, even though false, has NO conceivable observation that could refute it.

If there were such a theory (even though false, NO conceivable observation could refute), THEN such a theory would NOT be properly regarded as empirical, or diagrammed out:

(False :arrow: NO COR) :arrow: NOT PRE

Answer choice C gives us such a theory. Even if psychoanalysis were false, NO conceivable observation could refute it. Thus, the necessary condition of the contrapositive applies to psychoanalysis as well: it is NOT properly regarded as empirical.

I hope this helps!

Jeremy
 lathlee
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#74468
For the record in this scenario,

(COR :arrow: NO False) :arrow: NOT PRE --- is just as correct contrapositive as --- False :arrow: NO COR) :arrow: NOT PRE

Due to the nature of OR rule
 Jeremy Press
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#74469
Hi lathlee,

The diagram: (COR :arrow: NOT False) :arrow: NOT PRE is not actually an accurate depiction of the contrapositive.

That's because COR :arrow: NOT False is not an accurate negation of False :arrow: COR. This is because a necessary condition can always theoretically occur with or without its sufficient condition. So stating that a necessary condition occurs without a sufficient condition is not a true negation of the conditional relationship (because the conditional relationship allows that to happen). Better to stick solely with the form of contrapositive I diagrammed and explained above.

I hope this helps!

Jeremy
 lathlee
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#74471
Hi. Sorry actually I mistyped.

I meant to say following :

Negative False. :arrow: Corn :arrow: NOT PRE is just as correct contrapositive as --- False :arrow: NO COR) :arrow: NOT PRE

Due to the nature of OR rule
 Ari
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#80766
Hello,

I chose answer choice D. I do see how C is correct. Is D wrong because it is a mistaken negation? I noticed "unless," but I guess I did not think the arrangement of D was impacted by the conditional logic. It would impact it though because just because a theory has conceivable observations that would prove it to be false does not mean it has to be empirical? However, if it is empirical it MUST have conceivable observations that would refute it? Is this correct logic? Thanks!
 Adam Tyson
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#81189
Correct, Ari! Answer D does mistakenly reverse the conditional relationship, which is why it does not follow the rule set out in the stimulus and does not, therefore, have to be true. Good work!

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