How to Let the Manas Deliberate on Problems Without Affecting Sleep?

If you want to assign some tasks to the manas before sleep—so that the manas can contemplate a question during sleep—without affecting your sleep, then the manas needs to be very familiar with this question, understanding what its content is, so that the mind consciousness does not need to help analyze the problem again, nor transmit any further information. Moreover, this question should not be urgent to resolve; there is no need to know the answer right away. In this way, the manas will feel at ease letting the six consciousnesses cease.

After assigning the task and posing the question to contemplate, do not do anything else, and do not think about anything else either; just go straight to sleep, letting the manas hold only this one matter in mind, unaffected and unobscured by other things. When the manas needs to activate the mind consciousness to assist its contemplation, it is certainly because it is not yet very familiar with the problem and cannot find a method or direction for solving it, and thus requires the mind consciousness to help analyze and provide information for reference. If the manas is very familiar with the problem and has a method for solving it, then even if the mind consciousness wants to help analyze it, the manas will not use it, considering it an obstruction.