public Negation(Term a) { _left = a; }
public Disjunction(Term a, Term b) { _left = a; _right = b; }
public Implication(Term a, Term b) { _left = a; _right = b; }
public Negation(Term a) { _left = a; }
public Disjunction(Term a, Term b) { _left = a; _right = b; }
public Implication(Term a, Term b) { _left = a; _right = b; }