The simplicity of the necessary-by-itself is one of the most important issues discussed by Islamic philosophers and theologians. It has also a prominent position in transcendental wisdom (Hikmat e Motaaliyeh). Allameh Tabatabai, as a transcendental philosopher, puts emphasis on the real simplicity of the divine nature and provides a lot of arguments for it. With the analysis of the foundations of his arguments, it is demonstrated that two different views are expressed on this issue: one is the simplicity of the necessary-by-itself and the arguments for its affirmation based on the positive attitude to quiddity; the other is the simplicity of the necessary-by-itself and the arguments for its affirmation based on the negative attitude to quiddity. It seems that Allameh Tabatabai assumes the second view which is free from the first view’s difficulties as it proves simplicity in a direct way. The present article aims at delineating the second view and demonstrating its superiority to the first one.