In Quatrain 34 from Rubaiyat of Omar Khayyam, he says that this world and the life on it that we have, is like a circle that no one can find its start or end. The cycle of coming and going is going on constantly non stop. What is this coming and going for? Let’s read the poem in Persian first and then its translation.

در دایره‌ای که آمد و رفتن ماست
او را نه بدایت است، نه نهایت پیداست

کس دم نزند در این معنی راست
کاین آمدن از کجا و رفتن به کجاست

Here's the translation of the quatrain from Omar Khayyam to English:
Within this circle where we come and go, Neither beginning nor end can be found.
No one speaks about the true meaning of this, From whence this coming, and where this going.
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