 The Endoporeutic reading allows us to get the first reading only, but we may obtain different sentences by the Multiple Readings. Of course, all of these sentences are logically equivalent. Here is an interesting point: In the case of symbolic systems, we need to prove the equivalence among the above sentences by using inference rules. But, derivation processes are dispensable in the case of the Alpha system when the Multiple readings are  adopted.[30]  Hence, having the  clause 4(b)  above in addition to  clause 3  and  clause 4(a)  is not redundant, but instead highlights a fundamental difference between the Alpha system and a symbolic language with various connectives (see Shin 2002: §§4.3.2, 4.4.4, and 4.5.3).