The soul knows itself as its own bodies and knows other souls as their bodies, thereby sustaining a world of duality where there is sex, competition, aggression, jealousy, mutual fear, and self-centered exclusive ambition. Hence self-knowledge of the soul by means of any external sign is a source of untold confusion, complication, and entanglement.
This form of ignorance may be illustrated by means of the famous pumpkin story referred to by the Persian poet Jami in one of his couplets. Once upon a time there was an absentminded man who had no equal in forgetting things, even his own identity. He had an intelligent and trusted friend who wanted to help him to remember himself. This friend attached a pumpkin to his neck and said, "Now listen, old man, one day you might completely lose yourself and not know who you are. Therefore, as a sign, I tie this pumpkin around your neck so that every morning when you wake up you will see the pumpkin and know that it is you who are there."
Every day the absentminded man saw the pumpkin upon waking in the morning and said to himself. "I am not lost!" After some time, when he had become used to self-identification through the pumpkin, the friend asked a stranger to remain with the absentminded man, take the pumpkin from his neck during his sleep, and tie it around his own neck. The stranger did this; and when the absentminded man woke up in the morning, he did not see the pumpkin around his neck. So he said to himself, "I am lost!" Then he saw the pumpkin on the other man's neck and said to him, "You are me! But then who am I?"
This pumpkin story offers an analogy to the different forms of false self-knowledge growing from identification with one of the bodies. To know oneself as the body is like knowing oneself by means of the pumpkin. The disturbance caused by ceasing to identify with the gross, subtle, or mental body is comparable to the confusion of the absentminded man when he could no longer see the pumpkin around his own neck. The beginnings of dissolution of the sense of duality are equivalent to the man's identification of himself as the stranger who wore his pumpkin. Further, if the absentminded man in the story were to learn to know himself through himself independently of any external sign, his self-knowledge would be comparable to the true Self-knowledge of the soul — which, after ceasing to identify with the three bodies, knows itself to be none other than infinite God. Arriving at such Self-knowledge is the very goal of creation.
(Discourses, pp. 139-140