The Goodness of Reality hypothesis does imply that if you want to defend yourself, feeling tanha about being attacked is suboptimal because it biases your judgments about the most effective ways to respond.
A bias only makes your responses suboptimal if the bias is wrong for the situation; if it biases you toward good responses, it makes your behavior more optimal. I touched upon this in my old post on insight meditation:
Cognitive fusion is a term from Acceptance and Commitment Therapy (ACT), which refers to a person “fusing together” with the content of a thought or emotion, so that the content is experienced as an objective fact about the world rather than as a mental construct. The most obvious example of this might be if you get really upset with someone else and become convinced that something was all their fault (even if you had actually done something blameworthy too).
In this example, your anger isn’t letting you see clearly, and you can’t step back from your anger to question it, because you have become “fused together” with it and experience everything in terms of the anger’s internal logic. [...]
Cognitive fusion isn’t necessarily a bad thing. If you suddenly notice a car driving towards you at a high speed, you don’t want to get stuck pondering about how the feeling of danger is actually a mental construct produced by your brain. You want to get out of the way as fast as possible, with minimal mental clutter interfering with your actions. [...]
Cognitive fusion trades flexibility for focus. You will be strongly driven and capable of focusing on just the thing that’s your in mind, at the cost of being less likely to notice when that thing is actually wrong.
Tanha seems to cause cognitive fusion/fixation on narrow aspects of the situation, and it seems probable to me that it evolved to do that because there are many situations where that’s beneficial. If you get attacked, the tanha may help focus your attention on the need to defend yourself and how to best do that.
Of course, a lot of the ways we’re attacked today are a poor fit to the kinds of situations tanha evolved to be adaptive for (e.g. getting very upset when someone verbally assaults you on social media is probably not the optimal response). But there are still quite a few purely physical fights happening in the world, and in those I’d guess tanha to be more likely to be adaptive than not.
A bias only makes your responses suboptimal if the bias is wrong for the situation; if it biases you toward good responses, it makes your behavior more optimal. I touched upon this in my old post on insight meditation:
Tanha seems to cause cognitive fusion/fixation on narrow aspects of the situation, and it seems probable to me that it evolved to do that because there are many situations where that’s beneficial. If you get attacked, the tanha may help focus your attention on the need to defend yourself and how to best do that.
Of course, a lot of the ways we’re attacked today are a poor fit to the kinds of situations tanha evolved to be adaptive for (e.g. getting very upset when someone verbally assaults you on social media is probably not the optimal response). But there are still quite a few purely physical fights happening in the world, and in those I’d guess tanha to be more likely to be adaptive than not.