What decides where will be reborn?
The most important factor, but not the only one, influencing where we will be reborn and what sort of life we shall have, is kamma. The word kamma means 'action' and refers to our intentional mental actions. In other words, what we are is determined very much by how we have thought and acted in the past. Likewise, how we think and act now will influence how we will be in the future. The gentle, loving type of person tends to be reborn in a heaven realm or as a human being who has a predominance of pleasant experiences. the anxious, worried or extremely cruel type of person tends to be reborn in a hell realm or as a human being who has a predominance of painful experiences. The person who develops obsessive craving, fierce longings, and burning ambitions that can never be satisfied tends to be reborn as a hungry ghost or as a human being frustrated by longing and wanting. Whatever mental habits are strongly developed in this life will continue in the next life. Most people, however, are reborn as human beings.
The last sentence seems to contradict the Buddha's teaching that rebirth in the human world is exceedingly rare, and I gather that most Buddhists believe very few people are likely to come back as humans next time around. So initially when I came across Ven. Dhammika's statement, I figured this was an idiosyncratic teaching of his own and not in line with the general understanding.
However, now I'm not so sure. Here's why:
1. If he is talking about people here on the earth that we know, then we have to consider that Earth is just one of a potentially infinite number of locations at which beings can be reborn. It's s a speck of sand in the River Ganges, so to speak. Therefore, even if all currently living persons on planet Earth were able to come back as humans, human birth would still qualify as rare in mathematical terms.
2. Even if we include humans in different world systems, the statement would still be supportable as long as the other planes of existence were much, much larger compared to the human plane. That is, if the number of humans throughout all the world systems was extremely small compared to the number of all other beings, then the blind turtle parable would still be true even if Ven. Dhammika is correct.
His interpretation also makes intuitive sense for another reason: the balance of kamma accumulated over the course of an average human life probably evens out. Yes, there are particularly virtuous people, and particularly evil people. Generally speaking, though, people try to be good to the extent that their circumstances allow them to, and our lives are a mixture of the wholesome and unwholesome. Therefore the weight of kamma accumulated during this lifetime doesn't really seem sufficient to override the kamma which brought us to this realm in the first place. It seems more logical to say that extraordinary virtue is needed in order to rise to the heavens, and a heavy weight of unwholesome kamma is needed in order to regress to the lower realms.
What do you think?