Flexibility of the mind is defined as the ability to transition from thinking about one concept to another. Obviously the opposite of flexibility is rigidity. When our thoughts are rigid, we may have a hard time shifting our thoughts to accommodate in-coming changes. A rigid mind may reject the point of view or perspective of others around them. In both the Yoga Sutras & the Bhagavad Gita, a rigid mindset is referred to as Avidya. This translation of Avidya is ignorance or incorrect knowledge.