marble

What is Koan?

|>       "A living man sits and does not lie down (all the time),
|>        While a dead man lies down and does not sit.
|>        On this physical body of ours
|>        Why should we impose the task of sitting?"
|>
|>                         - Hui Neng, 6th Chinese Ch'an Patriarch

|> Pray tell us what is dhyana 

fervent prayer

|> and what is a profitable practice if you think you understand
|> the meaning of Hui Neng.

sitting can be a profitable practice.  do not impose it as a task

|  Dhyana is not resting on a single thing, not ignoring a single thing;
|  it is knowing what you are doing, and not knowing you are doing it.
|  It is the state of your mind operating on its own without any 
|  interference from you.

|  A profitable practice is one in which the benefits exceed the costs.

a marble touches the marble