During the period of Guru Nanak, there were different and mutually opposing ideas of the concept of Reality. For Guru Nanakji, how to describe the otherness of the created beings without decreasing the ultimate unity of Reality was a difficult task. For Nanak, the ultimate reality was a progressive process that combines the personal and the impersonal dimensions. This dynamic metaphysical approach describes the otherness of the demonstrated things and at the same time, the impersonal aspect of the Ultimate Reality.
After Guru Gobind Singh, there were two schools of thought i.e. the Nirmala School which promoted non-dualistic interpretation of Reality, and the Giani School, which supported the explanatory interpretation of the Adi Granth. Both these schools have done a lot of work in the development of the Sikh tradition and Sikh philosophy. The basic belief designed by Guru Nanak is always presented at the start of the Adi Granth, which talks about the fundamental description of Sikh metaphysics. The fundamental tenet delivered by Nanak blends the unity of the personal God and the spirit of impersonal idealism. The personal and the non-dual nature of the Ultimate Reality is what lies in the Sikh scriptures.
The viewpoint of the unity of the Ultimate Reality is symbolized by the Sikh concept called Ikomkar, which is a blend of three terms, which are Ik means One, Om means the principal reason of the practical world and Kar means the creative viewpoint. In Sikh philosophy, Ikomkar describes the non-dual systematic unity in Sikh philosophy. There are various kinds of unity, which are aggregate unity or simply collection of units; mechanical unity or the units that are linked by an external agent; organic unity or units that are integrally associated. None of these is perfect unity as all of them are trans-relational. The perfect Unity is trans-relational, which means it exceeds all relations.
