We are looking at the 27th sarga of the Vairagya Prakarana of Yoga Vasishta.
Why do we call the world unreal?
Because the world is subject to individual perception.
To understand this, let us look at the time units of humans, Pitrus, and Devas.
One month of humans is a single day for the Pitrus.
15 days of Shukla paksha of a lunar month is their daytime, and 15 days of Krishna Paksha is their nighttime.
One human year is a single day for Devas.
6 months of Uttarayana is their daytime and 6 months of Dakshinayana is their nighttime.
Can you sleep for 15 days or 6 months at a stretch?
It is too long for us.
For them, it is regular.
4.32 billion years is just half a day for the occupants of Brahma Loka.
Even concepts like long, short, fast, and slow are subject to individual perception.
Studying for 3 or 4 hrs at a stretch may be normal for someone.
But sitting for half an hour may be a big deal for someone else.
This is why it is said that the world is unreal.
Had it been real, it would have been the same for everyone.
One hour would have felt the same way for every individual, Pitrus, Devas, and even the occupants of Brahma Loka.
That is not the case.
All these concepts: big and small, long and short, tall and dwarf, dark and bright, good and bad, expensive and cheap, wise and dumb, strong and weak, rich and poor, tasty and not tasty, harmful and harmless, friend and enemy - they are all perceptions.
But this is what the world is all about.
When you compare the two long and short, there is no fixed benchmark.
Length of a pencil you can take 6 inches as a benchmark and say that a ten-inch long pencil is long and a two-inch long pencil is short.
But using the same you can not say that a ten-inch long bus is long and a two-inch long bus is short.
For someone earning 6,000 rupees a month, spending 200 rupees on a single meal is costly but for a multi-billionaire, even 20,000 for a meal is nothing.
There is no benchmark or a gold standard for anything in this world.
And one major thing we keep ourselves occupied with is comparing.
This is good - that is bad, this is expensive - that is cheap, this is beautiful - that is ugly, this is great - that is mean.
We spend most of our time doing this comparison.
This is one of the reasons it is said that the world is not real.
It is a perception.
When my world is different from your world, then how can you call it real?
Lord Rama is asking in the Vairagya Prakarana of Yoga Vasishta.