Our thoughts define who we are. Yoga teaches us that every thought we have has an impact on us personally as well as the world around us. An optimistic outlook and the ability to focus create uplifting vibrations and a healthy, peaceful and joyful life. Yoga teaches us to strive to maintain a positive and serene mind by following the teachings of <strong>vedantic</strong> philosophy, a philosophy that teaches the unity of all creation or oneness of consciousness, and the practice of <strong>meditation</strong> —keys to achieving peace of mind and elimination of negativity in our lives.  Unless our mind is filled with positive thoughts higher spiritual knowledge and deep meditation are difficult to attain. When we harbour negative thoughts our mind becomes agitated and restless, our actions disturbed and unbalanced. They poison the very source of life and destroy the harmony, efficiency, vitality and vigour within us. Opposite thoughts of cheerfulness, joy and courage, heal and soothe. They increase our efficiency and mental power and allow us to live life to the fullest capacity. Yoga teaches us that our thoughts are the real cause behind our success and happiness in life. The lives we live and the type of experiences we have are the direct result of the way we think. Once we master the art of positive thinking, we are happy, harmonious and peaceful, and our ability to comprehend higher truths as well as to maintain a powerful meditation practice will follow.