When people are thinking, ''This is mine! This is mine!'' they feel happy. But when the thing that is ''mine'' is lost, then they will cry over it. This is the path for suffering to come about. We can observe this. If there is no ''mine'' or ''me,'' then we can make use of things while we are living, without attachment to them as being ours. If they are lost or broken, that is simply natural; we don't see them as ours, or as anyone's, and we don't conceive of self or other.
This isn't just talking about a mad person; this is someone who is diligent. Such a person really knows what is useful, in so many different ways. But when others look at him and try to figure him out, they will see someone who is crazy.
When Sumedho looks at lay people, he will see them as ignorant, like little children. When lay people consider Sumedho, they will think he is someone who's lost it. You don't have any interest in the things they live for. To put it another way, an arahant and an insane person are similar. Think about it. When people look at an arahant, they will think he is crazy. If you curse him, he doesn't care. Whatever you say to him, he doesn't react - like a crazy person. But crazy and having awareness. A truly insane person may not get angry when he is cursed, but that's because he doesn't know what's going on. Someone observing the arahant and the mad person might see them as the same. But the lowest is mad, the very highest is arahant. Highest and lowest are similar, if you look at their external manifestation. But their inner awareness, their sense of things, is very different.
Think about this. When someone says something that ought to make you angry and you just let it go, people might think you're crazy. So when you teach others about these things, they don't understand very easily. It has to be internalized for them to really understand.