Buying tools: Start by buying the absolute cheapest tools you can find. Upgrade the ones you use a lot. If you wind up using some tool for a job， buy the very best you can afford.

世界如此不快乐是因为它对真实的自我无知。人的真正本性是幸福的。幸福是与生俱来的在真实的自我中。人对幸福的追求是对他真实自我的无意识的追求。