Optoelectronics, often known as photon-based electronics, is well recognised for being more effective than conventional electronics for communication. To create a superfast computer, several devices have previously been developed in the field of all optical computing systems. Here, we have put forth an all-optical 2:1 multiplexer with the usage of nonlinear material exhibiting a strong ac Kerr effect and 2:1 Multiplexer (MUX) based all optical -photonic switches - NOT, OR, AND, NAND, NOR etc. The sole method for building combinational logic circuits is to utilise MUX. This work is made simpler by the Shannon decomposition theorem than by other approaches. In this study, input and output are expressed as the presence of a light signal with a prefixed intensity as binary 1 and the absence of a light signal as binary 0 using an intensity-based all-optical device and positive logic. Since the system is entirely optical, our current design enables very-high speed (terahertz) computation, which is not possible with typical semiconductor electronic switches. Validation through mathematical computations-based PYTHON simulations establishes the efficacy of the proposed approach. This research holds promise for applications in industrial and commercial contexts, offering enhanced performance and versatility.