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General questions relating to LSAT Logical Reasoning.
 Jay
  • Posts: 46
  • Joined: Jan 09, 2020
|
#84609
Hi, one quick conditional logic question!

No act can be seen as altruism unless the person seeing it is himself selfless.

So,

"No act can be seen as altruism" = "Act -> Not altruism"

Negation of this would be "Act -> altruism."

So, can I diagram "No act can be seen as altruism unless the person seeing it is himself selfless" as...

"(Act -> altruism) -> seeing it himself selfless" ?

Thank you!
 Jeremy Press
PowerScore Staff
  • PowerScore Staff
  • Posts: 1000
  • Joined: Jun 12, 2017
|
#84635
Hi Jay,

You're carving this one up a bit too much, and, in doing so, you're making the core idea contained in the statement more complicated and harder to understand. Resist the tendency to create a "nested conditional" (like your final diagram) unless it's absolutely necessary. Instead rely on the meaning of the ideas in the conditional statement.

Start with the "unless" as your point of division of this statement. What idea (what notion) is "unless" modifying? It's modifying the idea of someone who sees an act as altruistic being selfless themselves. What is that telling me is truly necessary in this context? It's telling me that selflessness (being selfless) is necessary. Let's diagram that simply as:

:arrow: Be selfless

Now we have to figure out what selflessness is necessary for. In other words, we have to identify the sufficient condition. One way to do this is from trying to read the statement contextually: selflessness is necessary for seeing an act as altruism. Another way to do this is simply to state the negation of the phrase preceding the "unless," using that phrase as the sufficient condition (this is the PowerScore Unless Equation). What is the logical negation of the phrase "No act can be seen as altruism?" It would be "An act can be seen as altruism," which I'd probably simplify in this context to "an act seen as altruism." Let's diagram that even more simply as:

See act as altruism :arrow: Be selfless

What is the interpretation of that statement? If someone is going to see an act as altruism, then they must be selfless. That fits the notion conveyed by the original statement quite well.

Remember that the goal here is not simply to formulaically produce arrow diagrams. Rather, it's to understand the conditional relationship between the ideas being presented. My goal is to "translate" the statement into a simple "if...then..." relationship, if at all possible. That's very possible here, using the steps I outlined above.

I hope this helps!

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