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In [1]:
import proveit
from proveit import defaults
from proveit import A
from proveit.logic.equality import not_equals_contradiction
theory = proveit.Theory() # the theorem's theory
In [2]:
%proving from_not_false
With these allowed/disallowed theorem/theory presumptions (e.g., to avoid circular dependencies), we begin our proof of
from_not_false:
(see dependencies)
In [3]:
defaults.assumptions = from_not_false.conditions
defaults.assumptions:
In [4]:
AneqF = defaults.assumptions[-1]
AneqF:
In [5]:
AneqF.affirm_via_contradiction(A)
from_not_false may now be readily provable (assuming required theorems are usable).  Simply execute "%qed".
In [6]:
%qed
proveit.logic.booleans.from_not_false has been proven.
Out[6]:
 step typerequirementsstatement
0generalization1  ⊢  
1instantiation2, 3, 4,  ⊢  
  :
2axiom  ⊢  
 proveit.logic.booleans.implication.affirmation_via_contradiction
3assumption  ⊢  
4deduction5  ⊢  
5instantiation6, 7, 8,  ⊢  
  : , :
6theorem  ⊢  
 proveit.logic.equality.not_equals_contradiction
7instantiation9, 10  ⊢  
  :
8assumption  ⊢  
9axiom  ⊢  
 proveit.logic.booleans.negation.negation_elim
10assumption  ⊢