minor changes
fix a bug in capture avoiding substitution
need to investigate strong induction
need to go with the old version of contradiction; and need some arithmetic facts as well, it is a bit tricky
for a moment, I almost think they are right and I am wrong, huh, it turns out I am right in the end. I should believe in myself more
the interactive environment is giving hand ache
prove a lemma that nothing in between n and succ n
how would I simplify the effort of proving a theorem?
find a bug, which unintentionally capture variable after unfold the definition that has a binder..
false alarm, scope will take care of the bussiness; while, I need to think about tactic for sum
proved trichotomy; found a bug in naiveSub
fixed a bug introduced by the let bind in the proof
proved a key lemma for strong induction
half way to strong induction.
nail the strong induction.
strungling on one lemma
fix bugs and add a proof of strong induction.