It's encouraging that his students aren't showing any visible sign of emotional disturbance at the prediction or at failing to overcome it; they have some traces of dath ilani dignity, at least. Keltham was wondering whether a lack of training in dignity would require him to back off a little on challenges like those, but his students' dignity is unperturbed so far as he can see.
\ h. t3(h) -> t2(h)
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\ h. ~t2(h) -> ~t3(h)
"So long as we have this reasoning tactic in our tactical repertoire - go ahead and take a moment to convince yourself that you couldn't cast an illusion violating it - we can combine it with our previous rule to get the combined rule we wanted:"
[1] \ z. t1(z) -> ~t2(z) (Premise)
[2] \ h. t3(h) -> t2(h) (Premise)
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[3] \ h. ~t2(h') -> ~t3(h') (modus tollens [2])
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[4] \ q. t1(q) -> ~t3(q) (syllogism [1], [3])
"Anyone want to propose yet another universal rule? Here's some other shorthand language to help you express yourself:"
blue(k) \/ red(k) "k is blue or k is red"
blue(k) /\ ~red(k) "k is blue and k is not k"
\k. ~(blue(k) /\ red(k)) "for every k, it is not the case that (k is blue and k is red)"
blue(k) -> small(k) "if k is blue, then k is small"
~~~blue(k) "it isn't wrong that k is not blue"