What is the definition of "limit of consciousness" as proposed by Herbart?

The concept of "limit of consciousness" as proposed by Herbart pertains to the idea that not all ideas or thoughts can rise to the level of awareness; they must have sufficient strength or intensity to do so. This means that for an idea to enter conscious thought, it needs to be powerful enough to break through the threshold of consciousness. Herbart believed in a hierarchy of mental activity where some thoughts remain in the subconscious unless they have enough force to gain attention and become conscious. This notion emphasizes the selective nature of consciousness, which can only process a limited amount of information at any given time. The other choices do not accurately capture Herbart's focus on the strength of ideas as a determining factor for their presence in consciousness.