Then where is the reality of a chair, if my idea of a chair is an illusion?
Light strikes the chair and is reflected into your eye, where is is focused onto your retina. The cells in your retina convert the light into electrical impulses in your optic nerves, and those impulses travel to your brain. All that you actually “see” are those electrical impulses. Similarly for all your other senses, all you can actually sense are electrical impulses in your sensory nerves.
The brain is good at pattern-matching. When it sees a certain pattern of incoming impulses it matches that pattern to a similar pattern it has stored in its memory. That internal pattern has the label “chair” assigned to it.
The actual chair is an external object. What we have inside our brains is a pattern of electrical impulses and an attached label: “chair”. The two things, external and internal are different.
The illusion is to think that those two very different things are actually the same. Just as the water you ‘see’ in a mirage is not water, so the ‘chair-pattern’ inside your head is not a chair.
Why am I better off for rejecting reality?
You are better off accepting the reality that the pattern inside your head is not actually reality.
Here is a Zen story:
On a cold winter night, a big snow storm hit the city and the temple where Dharma Master Dan Xia served as a Monk got snowed in. Cut off from outside traffic, the fuel delivery man could not get to the Zen Monastery. Soon it ran out of heating fuel after a few days and everybody was shivering in the cold. The monks could not even cook their meals.
Dan Xia began to remove the wooden Buddha Statues from the display and put them into the fireplace.
“What are you doing?” the monks were shocked to see that the holy Buddha Statues were being burnt inside the fire place. “You are burning our holy religious artefacts! You are insulting the Buddha!”
“Are these statues alive and do they have any Buddha nature?” asked Master Dan Xia.
“Of course not,” replied the monks. “They are made of wood. They cannot have Buddha Nature.”
“OK. Then they are just pieces of firewood and therefore can be used as heating fuel,” said Master Dan Xia. “Can you pass me another piece of firewood please? I need some warmth.”
The next day, the snow storm had gone and Dan Xia went into town and brought back some replacement Buddha Statues. After putting them on the displays, he began to kneel down and burn incense sticks to them.
“Are you worshipping firewood?” asked the monks who were confused about what he was doing.
“No. I am treating these statues as holy artefacts and am honouring the Buddha,” replied Dan Xia.
Do those statues match the “holy Buddha Statues” pattern or do they match the “firewood” pattern? It is important not to confuse internal patterns with external objects. Thinking that the two are the same can lead to suffering.
rossum