A Hindu accepts the Vedic (one who accepts the Veda teachings) scriptures as his or her religious guidance. Anyone can certainly gain benefit from the wisdom of the Hindu tradition. It does not demand religious affiliation. However, the benefit of the church is a long-standing tradition (it is the world's oldest religion) that benefits a community as a whole. Harmony exists in those communities where Avaidika schools are specifically non-Hindu (while geographically Indian) — Buddhism, Jainism and the atheistic Charvaka school. None of these schools accept the Veda.
All those traditions and all those disreputable systems of philosophy that are not based on the Veda produce no positive result after death; for they are declared to be founded on darkness. All those doctrines differing from the Veda that spring up and soon perish are ineffectual and misleading, because they are of modern date.This interpretation of Veda and non-Veda seems contrary to the position of an "accepting" religion. After all, there's no confusion that Hindus and Muslims do not get along.
Hinduism considers the world we live a projection of God. It is unreal (an illusion). It is unreal because it is unstable, unreliable, impermanent, and illusory. It is unreal because it hides the truth and shows us things that lead to Ajnana (ignorance). It is unreal because it changes every moment. What is now is not what is next.
Hindu believe it unwise to base our lives around such an unstable world. If you spend your precious life for the sake of impermanent and unreliable things, you are bound to regret in the end having wasted your life in the pursuit of emptiness. The real world lies beyond our ordinary senses where our existence would be eternal and where things would not change the way they do in this plane.
This particular Hindu philosophy is very simple, but enormously difficult to pursue. After all, what is illusion? Does it mislead you into wrong thinking and wrong actions, which conversely leads to wickedness. This world precisely does that. Is that the illusion? The world also offers happiness. But this too is an illusion. Happiness and want lead to suffering (no Yoda jokes). Did the ancient yogi know something about the transparent nature of "getting what you want."
Principles and Commandments
Hinduism can be distilled into five principles and ten commandments and these form the foundation of the Sanatana Dharma.
1. God Exists.
There is one absolute OM.
There is one Trinity — Brahma, Maheshwara (Shiva), Vishnu
Several divine forms
2. All human beings are divine.
3. Unity of existence through love.
4. Religious harmony.
5. Knowledge of the three Gs.
Ganga (sacred river), Gita (sacred script), Gayatri (sacred mantra)
1. Satya (Truth)
2. Ahimsa (Non-violence)
3. Brahmacharya (Celibacy, non-adultery)
4. Asteya (No desire to possess or steal)
5. Aparighara (Non-corrupt)
6. Shaucha (Cleanliness)
7. Santosh (Contentment)
8. Swadhyaya (Reading of scriptures)
9. Tapas (Austerity, perseverance, penance)
10. Ishwarpranidhan (Regular prayers)
The caste system was abolished by Indian law in 1949. Older people and those still living in rural India, still respect this very non-Western tradition.
Each Hindu belongs to one of four Varna (social castes), plus a fifth group called the "untouchables." They also are born into a Jãtis. One's Jat determines much. It tells him what work he can take on, who he may associate with, and even whether or not he can marry someone. The system is so rigid, a person is born into the Jat and Varna of their family, marries into it, and dies within it, with no possibility of upward mobility.
In decreasing status, the Varna:
Brahmins (the priests and academics)
Kshatriyas (rulers, military)
Vaishyas (farmers, landlords, and merchants)
Sudras (peasants, servants, and workers in non-polluting jobs).
The Dalit are considered outcasts, outside the caste system. Sometimes called Harijan (children of God), they are the polluted… the untouchables. Some believe that even contact with the shadow of a Dalit polluts ones soul. Check out Slumdog Millionaire for more of this.
Despite the government's attempts to outlaw the practice, the caste system still keeps the Dalit down. Considering it a form a slavery, many Dalit have converted to Buddhism and Christianity, angering Hindu radicals who have turned to violence and murder as a way of shuning proselytizing religions.
And while this is abhorrent, it's important to note that Hindu culture still (to this day) does not value women. The rates of infanticides of children is rampant. Ironic, given the sheer volume of babies born in India. Whether this comes into play in your games… well… let's hope it doesn't.