Logical Reasoning

PT13 · S2 · Q10 Every political philosopher of the

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Every political philosopher of the early twentieth century who was either a socialist or a communist was influenced by Rosa Luxemburg.

Statements

conditional (every)

20th cent. political philosopher influenced and socialist / communist → by R.L.

conditional (no A's are B = all A's are ~B)

influenced → didn't advocate by R.L. totalitarian state

Evaluate

Whenever we're doing Must Be True, we're primarily reading for any Conditional / Causal / Math-y language.

This had two conditional claims (we could also think of Every / No as quantifiers, if we want, but they are conditional-strength quantifiers).

Whenever we see conditionals, we have two things on our mind: 1. Can I chain this conditional to another one? 2. Can I apply this conditional to a provided fact?

Both of these claims are conditional, and they have an overlapping term ("influenced by Rosa"), so we should see if we can chain them , and indeed we can.

20th cent PP → influenced → didn't advocate and soc/comm by R.L. totalitarian state

Goal

We can probably expect some illegal reversals and negations in the wrong answers. The correct answer will probably reward us for putting this chain together by connecting the 1st to 3rd thing, possibly by contrapositive.

10.

If the statements above are true, which one of the following must on the basis of them also be true?

  1. Correct

    No early-twentieth-century socialist political philosopher

    Why this is right

    This answer is saying, 20th century PP ? didn't advocate and socialist totalitarian state That's something we can derive from our chain. It's connecting the first idea to the third. 20th cent PP ? influenced ? didn't advocate and soc/comm by R.L. totalitarian state We know that every political philosopher of the 20th century who was socialist was influenced by Rosa, and we know that no one influenced by Rosa advocated a totalitarian state.

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

    67% picked this

  2. Every early-twentieth-century political philosopher who

    Unknown Trigger

    This answer puts some language from the 1st and 3rd idea into a trigger, creating a relationship we can't justify. We knew this: 20th cent PP ? influenced ? didn't advocate and soc/comm by R.L. totalitarian state This answer is saying, 20th cent PP and didn't advocate ? influenced totalitarian state by R.L. We don't know whether all 20th century political philosophers who didn't advocate totalitarian states was influenced by Rosa. We only know that 20th century political philosophers who were socialist or communist were influenced by Rosa. But there might have been 20th century political philosophers who were capitalist that didn't advocate a totalitarian state, and maybe they weren't influenced by Rosa.

    10% picked this

  3. Rosa Luxemburg was the only

    Illegal Reversal Too Strong: the only

    This is an illegal reversal of the first sentence. We were told that all early 20th PP's who were socialist or communist were influenced by Rosa. But that doesn't mean they were only influenced by Rosa.

    2% picked this

  4. Every early-twentieth-century political philosopher who

    Bad Outcome Match

    This answer is saying, "Everyone from group X was a communist". The information didn't give us any means to prove that anyone was a communist. "Communist" was an idea in a trigger, not in an outcome. This answer is saying: 20th century PP; and influenced by Rosa ? communist and not socialist This is what we knew: 20th cent PP ? influenced ? didn't advocate and soc/comm by R.L. totalitarian state They're just doing a random Word Salad scramble of ingredients.

    11% picked this

  5. Every early-twentieth-century political philosopher who

    Bad Outcome Match

    This answer is saying, "Everyone from group X was a socialist or communist". The information didn't give us any means to prove that anyone was a socialist or communist. "Socialist or Communist" was an idea in a trigger, not in an outcome. This answer is saying: 20th century PP and didn't advocate ? socialist or communist totalitarian state This is what we knew: 20th cent PP ? influenced ? didn't advocate and soc/comm by R.L. totalitarian state They're just doing a random Word Salad scramble of ingredients.

    10% picked this

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