《庄子·内篇·齐物论》
所以说不如用事物的本然来加以观察和认识。用组成事物的要素来说明要素不是事物本身，不如用非事物的要素来说明事物的要素并非事物本身；用白马来说明白马不是马，不如用非马来说明白马不是马。
以指喻指之非指，不若以非指喻指之非指也；以马喻马之非马，不若以非马喻马之非马也。
Therefore, it is better to use the nature of things to observe and understand them. To use the elements that make up things to explain that the elements are not the things themselves is not as good as using the non-essential elements to explain that the essential elements are not the things themselves; to use a white horse to explain that a white horse is not a horse is not as good as using a non-horse to explain that a horse is not a horse.