Quora Answer: What is Buddhism in layman’s terms?
Buddhism is a heresy of the Indo-European worldview as expressed in Hinduism in India. In India Indo-European invaders ran into non-indo-european natives in an interesting clash of cultures which is ultimately summarized by the three gods Brahman, Vishnu and Shiva. Brahman summarized the ideas of God of the invaders, and Shiva summarized the idea of God of the indigenous Indians especially the Tamil’s. Vishnu was an attempt to work out a nondual compromise between the two extremely different worldviews.
Only Indo-european languages have Being (Sat). The buddhist revolt was to deny being to the Self (anatman). Interestingly it flourished at the same time as another similar heresy called Jainism. I have a theory that Mahayana Buddhism is basically a combination of Buddhism and Jainism. But this is not established. Anyway it shows that there was a time when Hinduism went through a crisis in which there were many breakaway religions that formed in response to Hinduism that was founded on the idea of Being (Sat Citta Ananda) and Buddhism was the most radical of these.
Interestingly Buddhism takes many themes and motifs from the Indo-european sources of Hinduism and transforms them giving them a new life within the buddhist worldview which is a worldview without Being. Since, buddhism had the sophistication of Hinduism but without its metaphysical baggage it was accepted in many non-indoeuropean cultures where it survived while in India it was reabsorbed into Hinduism based on the work of Nagarjuna who showed that Emptiness was at the heart of Logic. This gave rise to a transformation in Hinduism itself which was inaugurated by Shankara who basically interpreted Being as emptiness and was thereby able to create a unification of the various doctrines in the Upanishads by going up a meta-level. The concept of Nirguna Brahman was ultimately a concept of an empty Godhead. Similar to the ideas of Meister Eckhart in Europe.
Buddhism for all its sophistication was eventually found to be dualistic itself because of its idea of the dichotomy between the two truths and Dzogchen attempted to rectify that and further developed the already sophisticated theory of Emptiness. In china also there were attempts to come up with a synthesis between Taoism and Buddhism which is seen in Hau Yen Buddhism and also in Tien Tai Buddhism and the southern school of Zen.
Buddhism is very deep from a philosophical point of view, especially with respect to the critique of the concept of Being which is rampant in the Indo-european worldview, It is still relevant for us today as a critique of our concept of Being. And because it leads to nondual ways of looking at things which is foreign to our overly dualistic worldview. Also Buddhism is based on meditation and thus has an experiential content which makes it an extremely powerful antidote to the production of illusion rampant in the Western Worldview.
Another nondual heresy specially of the European Western worldview is Islam and within it Sufism. It is extremely interesting to compare the heresy of Hinduism, i.e. Buddhism, to Islam as the heresy of European Dualism. By comparing Taosim, the nondual heresy of Confucianism, and Buddhism, the nondual heresy of Hinduism, and Islam, the nondual heresy of European Western dualism to each other we get a synoptic overview of nonduality. Basically what we see in that comparison is that all worldviews start off with a series of dichotomies which they explore the permutations of working out the structural possibilities in those founding dichotomies. But at some point the occurs to someone the idea that there is a nondual alternative to all the other alternatives that is outside the permutational set, and this fundamentally transforms the dialogue between the different positions that are possible within the worldview. Taoism did that for China, Buddhism did that for Hinduism, and Islamic Sufism does that for the dominant European Western worldview. But what is most interesting is where these different nondual approaches have interacted and influenced each other. An example of that is DzogChen which attempted a critique of Emptiness in terms of the idea of Void from Taoism and Bon. Ultimately the idea of Emptiness is itself Empty and thus it turns back into the Void. Islam and Sufism on the other hand start from a completely different source to provide a deeper view of nonduality. But one cannot really understand Sufism without some prior understanding of other nondual ways.
The Buddhist Heresy basically says that Being does not exist, is an illusion, and what does exist is emptiness which is a nondual non-concept non-experience which is the background on which we see everything that does exist. Buddhism proves its case via meditational techniques which take one into alternate states of consciousness in which Being vanishes and other ways of looking at things that are nondual are seen to be a more basic way of looking at the things of this world and our place in it. The heresy of Buddhism is DzogChen which negates the difference between the two truths as a kind of meta-dualism returning emptiness to the void of Taoism and Bon.