Acharya Prashant begins by listing the four Yugas in the Vedic tradition: Satya Yuga, Treta Yuga, Dvapara Yuga, and Kali Yuga. He questions the common belief that these Yugas represent a historical passage of time. He explains that we have been led to believe that time is an external, objective entity that happens to us, something occurring in a clock or watch, outside of ourselves. This perception leads us to view the Yugas as fixed, linear periods, much like months in a calendar, with specific start and end dates, culminating in the current Kali Yuga. However, the speaker asserts that this conventional understanding is not how Vedanta perceives time. Vedanta does not regard time as an external entity. Instead, it primarily deals with only two concepts: the Atma (the Self) and the mind. He poses the question: if only the Atma and the mind exist, what is this third thing called time? He clarifies that time cannot be the Atma, because the Atma is changeless, whereas time denotes change. Therefore, from a Vedantic viewpoint, time is the mind. Based on this understanding, the four Yugas are not a linear progression or spans on a calendar but are states of the mind. The speaker defines each Yuga as a specific state of mind. Satya Yuga is when the mind is totally centered in the Self, the Truth. Treta Yuga is when the mind is identified with thoughts. Dvapara Yuga is identification with the body, and Kali Yuga is identification with the world (Samsara). The progression through these Yugas represents a movement progressively away from the center, which is the Self. In conclusion, Acharya Prashant explains that when the mind is closest to the center (the Truth), it is in Satya Yuga. When it is farthest from the center, it is in Kali Yuga. This implies that any individual can be in any of these Yugas at any given moment. One is not condemned to live in Kali Yuga. If you are living a Truth-centered life, you are in Satya Yuga. Conversely, if you are living a world-centered life, you are in Kali Yuga. This is the proper way to comprehend the concept of the four Yugas.