There is a deep psychological principle expressed in tantras, in the Kalacakra we have outer, inner and other Kalachakra. The idea exists in other tantras too, but its meaning is not often expounded or explained. When you are very familiar with something you are bound to see ousiders, the other, as possessing the thing you think you don't have yourself. Reality is utterly nondual. The essence of Dharma moves into, or is seen in, the other. You begin to see it in Jainism, as an example. You have become too familiar with buddhism, so your mind sees it somewhere else. This is a real phenomenon. There is no absolute separation between any of the ideologies and spiritual systems in this world. The other dharma can be anything.