A person opened a room i the dark night. Suddenly he saw a snake and was afraid and began to step back. He just hit the light switch. As soon as the room was lit, the snake disappeared. Actually there was no snake, it was a rope..
It is our mind that perceived snake. The snake was superimp osed on the rope.
Is the snake real? No. Snake cannot exist without rope, but rope can exist without snake.
Now, if we see the snake and scream that 'i am seeing the rope'. Is it right.
lit the lamp of knowledge and the snake (born out of ignorance) will disappear without any effort instantly. But to lit the lamp one has to make effort. Running away or catching the snake (to earn something out of it) will be there (i.e. there will be mental effort) till we realise that it is a rope and not the snake.. Realisation occures instantly without effort and without delay.
There is no connection between snake and the rope. The snake never existed in reality, but snake is no different from the rope as it is superimposed on the rope. actually, snake is nothing but the rope (i.e. maya). But with clear mind, we can see the rope (SELF).
Adapted from Vivek Choodamani. This explanation also appears in Ramana's 40 verses on truth and even in the upnishads. It is the extreme explanation ( i have came across) and one of the best example by which one can explain the philosophy of non-duality.