The post on sexual pleasure mentioned the chariot model of yoga, which deserves its own post for a brief explanation. In the chariot model, the indriyas or senses are the horses, the mana or mind is the reigns, the buddhi or intellect that disciplines the mind is the driver, and the atman or soul is the passenger. The chariot can only move forward when the senses are surrendered to the mind, which is surrendered to the buddhi. Yoga is a vector, so direction is also an important factor, not only concentration in that direction. The direction is correct when the system is surrendered to the will of the atman, without attachments and desires of the mind in the way. This analogy describes the progression highlighted in Chapter 3, Slokas 42-43 of the Bhagavad Gita.