Answer by Suminda Sirinath S. Dharmasena for Translating "dukkha" as "reactivity"

When you have contact your consciousness react with some sensation or the other. If the sensation is unpleasant it is unsatisfactory, it is pleasant and changes or ends it is still unsatisfactory and if is neutral it is still unsatisfactory as wholesome and unwholesome roots which create future sensation are still present and the process of rebirth continues. If you crave to any of the sensations then you create suffering for the future, but if you are equanimous the seed of past karma which gave fruit will not find fertile ground to give results in the future.

So your ingrained habitual reaction to contact creates sensation which in turn creates sensation which lead to unsatisfactoriness with the contact and potential to create unsatisfactoriness is the future. If you develop equanimity in the face of pleasant and unpleasant sensations than craving and aversion and wisdom in the face of neutral sensation, than the habitual reaction then you can overcome in contact with sense objects, will prevent future occurrence of unsatisfactoriness.

I feel the authors is relating his understanding that the habitual reaction is what keep you rolling in misery in the future and this tendency to react creates misery now, but I feel the rendering is inaccurate as it is explaining causality by equating a result to the case, i.e., if A causes B then A is B.

See:

• Cūla Vedalla Sutta

pleasant feeling is pleasant when it persists, painful when it changes;

painful feeling is painful when it persists, pleasant when it changes;

neutral feeling is pleasant when there is knowledge of it, painful when there is no knowledge of it

• Pahāna Sutta

the latent tendency of lust should be abandoned in regard to pleasant feeling;

the latent tendency of aversion should be abandoned in regard to painful feeling;

the latent tendency of ignorance should be abandoned in regard to neutral feeling.

• Avijja Pahana Sutta 2

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