code: public double activationDegree(Term forTerm) {
          double result = 0.0;
          for (Activated activatedTerm : this.terms) {
              if (activatedTerm.getTerm() == forTerm) {
                  if (this.aggregation != null) {
                      result = this.aggregation.compute(result, activatedTerm.getDegree());
                  } else {
                      result += activatedTerm.getDegree(); //Default for WeightDefuzzifier
                  }
              }
          }
          return result;
      }
docs: Computes the aggregated activation degree for the given term. If the same
  term is present multiple times, the aggregation operator is utilized to sum
  the activation degrees of the term. If the aggregation operator is
  fl::null, a regular sum is performed.
  
  @param forTerm is the term for which to compute the aggregated activation
  degree
  @return the aggregated activation degree for the given term