What is Sane and Insane

A student asked Zen Master Seung Sahn: "What is sane and insane?"

Zen Master Seung Sahn: "If you're very attached to something, you are very crazy; if you're a little attached to something, you are a little crazy; if you're not attached to anything, you are not crazy.

In this world, everybody is crazy, because everybody is attached to 'I', but this 'I' doesn't exist, only made by our thinking. If you don't want to attach to your 'thinking I', and want to find your true nature, practicing Zen may help you."