Why is understanding motivations effective against judging others according to Buddhism?
I think that's human nature ... perhaps it's a truism of human nature ... but is not Buddhist doctrine.
Instead Buddhist doctrine is maybe about understanding or overcoming your own attachments and egocentricity, rather than trying to understand other people's motives. Sorry!
For example, there's a famous saying (in English) that "To understand all is to forgive all" -- that's listed as a Fake Buddha Quote. Usually the author (Bodhipaksa) would give passages from the suttas which are at least similar to the quote ... but he doesn't in this one, saying,
The Buddha doesn’t seem to have talked much about “forgiveness.” He talked much more about letting go of anger ...
Even so perhaps the cause ("why it's effective") is clear if you consider an invented example:
- Someone steals something from your shop
- You're angry at the loss, and blame the thief for being greedy and disrespectful
- If you find they stole because they were hungry, perhaps you are then more inclined to forgive them (perhaps because it's selfless, i.e. their hunger didn't necessarily involve "yourself")
I suppose that "understanding motivation" is a type of, or a cause of, compassion.
And I think that "compassion" is a feature of Buddhism -- not exactly 'doctrine' (e.g. that "you should feel compassion"), more like an 'axiom' (e.g. "do this because of course everyone feels compassion, it's human nature"), some kind of "Golden Rule"-like thinking, for example,
- All are afraid of the stick, all fear death. Putting oneself in another's place, one should not beat or kill others.
How can this idea be best applied in meditation? For example, how would meditating on the causes of suffering--to arouse compassion--be achieved?
My personal experience is that it doesn't work like that.
For example if I'm in conflict with someone because we both want something, or want different things, you might hope that my understanding their motive would make me more compassionate.
And in theory, intellectually, understanding the motives of the other person, and understanding our situation, works to some extent, sometimes ... but it's impermanent, not really stable ... because even if I understand or forgive them, I still can't get what I crave ... which fuels conflict ...
... so the more stable cessation of dukkha coincides with a cessation of my own craving, and cessation of fuelling own craving ... possibly replacing that craving with compassion ... but the generation-of-compassion alone (i.e. understanding other people's motives, without considering or reconsidering own motives such as craving) isn't enough.