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In [1]:
import proveit
from proveit import Conditional
from proveit import A, Q
from proveit.logic import TRUE, Equals
theory = proveit.Theory() # the theorem's theory
In [2]:
%proving implication_from_conditional
With these allowed/disallowed theorem/theory presumptions (e.g., to avoid circular dependencies), we begin our proof of
implication_from_conditional:
(see dependencies)
In [3]:
Q_eq_T = Equals(Q, TRUE).prove(assumptions=[Q])
Q_eq_T:  ⊢  
In [4]:
Q_eq_T.sub_right_side_into(Conditional(A, Q), 
                           assumptions=[Conditional(A, Q)]).simplify()
implication_from_conditional may now be readily provable (assuming required theorems are usable).  Simply execute "%qed".
In [5]:
%qed
proveit.core_expr_types.conditionals.implication_from_conditional has been proven.
Out[5]:
 step typerequirementsstatement
0generalization1  ⊢  
1deduction2  ⊢  
2instantiation3, 4, 5,  ⊢  
  : , :
3theorem  ⊢  
 proveit.logic.equality.rhs_via_equality
4instantiation6, 7, 8,  ⊢  
  : , :
5instantiation9  ⊢  
  :
6theorem  ⊢  
 proveit.logic.equality.substitute_in_true
7assumption  ⊢  
8assumption  ⊢  
9axiom  ⊢  
 proveit.core_expr_types.conditionals.true_condition_reduction