"That person's truth" yes, "objective truth" obviously not. Yes drunk people can talk a load of absolute sh*te but it's sh*te that, somewhere deep down, they believe. Basically alcohol can't "put anything into your head" that wasn't there already. Someone who starts spouting racist / sexist / homophobic crap when drunk for example, believes the same things when they're sober. They just have the sense not to say them out loud until those inhibitions are lowered.
Basically always be wary of a "nasty drunk" and the idea that it's something about "the drink" that turns them nasty. All it does is let the demons out

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