Ultimately, consciousness-based cognition considers all external environments perceived by human cognition to be invalid cognition. The so-called "direct perception" of the six senses is an artificial convention, only applicable within the realm of human brain cognition.
What we consider as direct perception through the six senses is a convention. For instance, what a normal human eye sees is defined as direct perception. However, from the ultimate Buddhist perspective, all six senses are invalid cognition. As it's said, "If the six senses were valid, what use would the noble path be?"
Therefore, it's utterly foolish to solely focus on changing the external environment without changing the mind. This is why Buddha so strongly emphasized and encouraged mind training. Some might ask, "If everyone trains their mind, who will produce food? What will we eat?" This is overthinking! If everyone could train their mind, this place would immediately become a pure land, and there'd be no need to worry about food.
Let's not even consider everyone training their mind. In ancient times, when people's minds were good, rice grew naturally. Why is life so difficult now? Don't blame the natural environment; human minds are in peril, too corrupted.
The corruption of human hearts is evident in many ways. I've lived for nearly 60 years, and although this is barely a drop in the ocean of history, it's enough to glimpse the bigger picture. The water I drank as a child is completely different from what we drink now. In my childhood hometown, there was a moat with crystal-clear water that we could scoop up and drink anytime. Now when I go back and look at it... Excessive greed leads to constant demands on the environment, endless production to satisfy ever-expanding desires. With more greedy people come factories, whose wastewater pollutes rivers, making the water undrinkable. This is the inevitable result of a vicious cycle. How many people now dare to drink water in the wild? Most carry bottled water - we messed up!
Which is a direct valid perception when looking at the sun: with sunglasses or without?
Buddhism doesn't encourage technological development because it recognizes that technology within the realm of the six senses is ultimately always invalid cognition. If we stay within the bounds of the six senses, we can still distinguish between valid and invalid cognition. For instance, when looking at the sun, people generally consider viewing without sunglasses as a direct valid perception and with sunglasses as invalid cognition. Another example is color blindness. When presented with a red ball and a green ball, those without color blindness can consistently differentiate them, while someone with red-green color blindness, due to their eye condition, cannot distinguish between red and green. According to this convention, their perception would be considered invalid. These are conventions that set categories.
However, human direct perception cannot actually see the sun. What we see is sunlight from eight minutes ago, as it takes that long for light to reach Earth from the sun. So, we never truly see the current sun.
Excerpted from: Cognition and Expression Part Three
