The Holy Science is a book of theology written by Swami Sri Yukteswar Giri in 1894. The text provides a close comparison of parts of the Christian Bible to the Hindu Upanishads, meant “to show as clearly as possible that there is an essential unity in all religions...and that there is but one goal admitted by all scriptures”.

The Holy Science consists of four chapters. The first is titled “The Gospel”, and is intended to “establish the fundamental truth of creation”. Next is “The Goal”. which discusses the three things all creatures are seeking: “Existence, Consciousness, and Bliss”.

Chapter three, “The Procedure”. is the most practical of the sections. It describes the natural way to live for purity and health of body and mind. The final chapter is called “The Revelation”. and discusses the end of the path for those who are near the “three ideals of life”.

Each yuga is an age of the world tracking the movement of the sun, Earth, and planets. Each age represents a different state of humanity. There are four yugas:

• Satya Yuga is the highest and most enlightened age of truth and perfection.
• Treta Yuga is the age of thought and is more spiritually advanced than Dwapara Yuga and Kali Yuga.
• Dwapara Yuga is an energetic age, although not a wise one. During this yuga, people are often self-serving and greedy. The age is marked by war and disease.
• Kali Yuga is the age of darkness, ignorance, and materialism. This is the least evolved age.

Today, The Holy Science is highly respected among those seeking to understand the relationships between world religions and cultures.