<p><a href=“1”>quote</a> The majority of courses are taught by professors? True.
(2) In each course taught by a professor, the professor teaches the class? True.
(3) In such classes the professors teaches for 2h30m per week? True.
(4) In lower-level classes where there is a recitation section, graduate students lead recitation for 1h15m per week? True.
Therefore,
(5) The professor spends 2x as much time teaching than the graduate student, when there is a recitation section.
(6) The professor is the only one teaching in a course without a recitation? True.
Therefore,
(7) The professor spends more time teaching than a graduate student.
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<p>Oh, this is already invalid, since (5) doesn’t follow from (1)-(4). I imagine you wanted to include:</p>
<p>(4a) The professor’s classes and the graduate student’s classes have the same quantity of sessions.
(4b) There are less recitation sections than class sections. </p>
<p>We also need to change premise 2 so as to show that graduate students teach the same amount as professors in lecture (I am guessing this is what you were trying to say, and were not simply avoiding mentioning the lecturing time of graduate students, since that seems like too simple a mistake for you to make), by avoiding a fallacy of equivocation between “professor” and “instructor”:</p>
<p>(3*) In such classes the instructor teaches for 2h30m per week? True.</p>
<p>Including these, we have a valid argument, since 1-4b (with 3* instead of 3) force 5, and 7 is valid from 6. Unfortunately, the argument is unsound, since 3* is false (not every class involves the same amount of teaching, as I noted earlier, some classes may involve 6 hours of teaching per week, some may only involve the amount of lecture hours, etc).</p>
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<p>Oh, you can take my posts however you want to, but I think this conversation is already not only offering advice to people about NYU and its students and teachers, but is <em>also</em> giving them some free instruction on the cooperative principle and logical inference! As well as how to formalize (and how <em>not</em> to formalize) an argument.</p>