The power of Reason

The word buddhi indicates intelligence, reason, or judgement. It is the power to discern where to enter and where to exit, what to do and what not to do, in pursuit of our rational self-interest. Buddhi tells us what is benign and what is malign, what liberates and what enslaves. Buddhi makes these crucial distinctions.
Above the fickly mind that likes and dislikes, accepts and rejects, with subjective caprice, there is cool, calm, objective buddhi - the voice of reason.
- A Comprehensive Guide to Bhagavad Gita, page 59

We all know the value of keeping a cool head when making important decisions. Rash, thoughtless behavior can often lead to mistakes, and sometimes disaster. Buddhi is the rational part of our thinking that calmly weighs the pros and cons, choosing the proper course of action through the use of reason. Buddhi is a vital part of spiritual awakening, helping to guide us to our ultimate understanding of ourselves and the world around us.