“All these Kleśa are variable in their potency.
They can be so weak, that they hardly matter.
Sometime they take a feeble form, when they can be easily contained.
If not they rise to dominance.  When in domination, only one takes over.
For example in the most evolved stage when Rāga is dominant,
other Kleśa such as Dveṣa are not apparent.”
– T Krishnamacharya commentary on Yoga Sūtra Chapter Two verse 4

“What is unpleasant is not desired.
The response of the mind is then to move away from it.
Whether in fact such a step did prevent Duḥkha is not immediately evident.”
– T Krishnamacharya’s commentary to Yoga Sūtra Chapter Two verse 8

“Dveṣa is the consequence
of Duḥkha from such as,
getting what you are not expecting or,
getting other than what you are expecting.”
– Reflections on Yoga Sūtra Chapter Two verse 8

“Each person has two forces Rāga and Dveṣa.
They are there to serve you, not you them.”
– TKV Desikachar on Bhagavad Gītā Chapter Three verse 34

“Attachment comes through pleasure. There’s nothing wrong with pleasure, but when we no longer have what gave us pleasure, or if there is some threat of losing it, attachment often appears.

Negation is a tendency to resist or reject after something bad has happened. It could be a fact, an idea or whatever, but if we were not comfortable with it, we resist. There is a strong relationship between attachment and negation, like heads and tails of a coin. Strangely, the more we are attached to something the more there is a likelihood to reject it later – when what we were expecting is not forthcoming heads becomes tails!

Fear is a very fundamental emotion which seems to have some special energy that can make it survive on its own. Fear exists independently of objects, they just give it something to fix on, like the wolf in Western fairy tales. There are two types of fear : fear of something, an earthquake, an illness, a wolf etc., and fear of losing something, a job, a loved one, prestige etc.

Fear, negation, attachment and association either alone or together create the conditions for suffering to erupt again and again. Suffering appears, disappears and re-appears forcing us to admit that something is missing and this pushes us to seek how to find it.”

– TKV Desikachar from unedited manuscript for ‘What are We Seeking?’