Harry asked: "Could it be meaningful to define two types (maybe even origins) of evil: "evil by choice" and "evil by nature"?"
'Evil nature' undercuts free will. That is: a man with an evil nature cannot be a free will. Such a man cannot truly be morally responsible. 'Evil by (or thru) choice' coherently 'fits' with free will.
"is it possible to be both: that, bit by bit, free decision by free decision, a free being chooses to become evil by nature?"
Well, I'd say he, bit by bit, free decision by free decision, chooses evil. His nature, as a free will, is self-corrupted thru choosing that which he knows is wrong. I have to hold out, however, the possibility he may choose to redeem himself. That is, even though thoroughly corrupted, he can still 'choose'. Being corrupted, then, is not irrevocable.
"Do you agree that evidence shows that psychopaths understand what's right and wrong perfectly well; it's just that they choose to use that understanding not to constrain their behaviour and choices but rather to manipulate others?"
I don't know. I guess it depends on the definition of psycho-/socio-path.
I believe the fields of psychology and neuropsychology are irredeemably flawed. Both (and others) are founded on the wholly unproven notion mind is just a product of brain. As such all such disciplines (and their disciples) ought be taken not with a pinch but with a fist full of salt. I'm not inclined to defer to definitions extending from these folks or their religion(s).
"On a dualist understanding (mine), in which consciousness survives biological death, is it in any case possible that psychopaths are - per question two above - "evil by choice" as well as "evil by nature": that, over (potentially aeons of) time, those souls which incarnate as psychopaths have, bit by bit, free decision by free decision, chosen to become evil by nature?"
That would be one (very neat) explanation.
"Thus, if a person by nature happened to desire being enslaved, raped, robbed, and even murdered, and to find those things literally pleasurable and even satisfying, then, although we very probably would consider that person to be perversely constituted, and would probably likewise consider to be perversely constituted anybody who indulged him/her in his/her desire to be enslaved, raped, robbed, and murdered, it arguably wouldn't be morally wrong in those circumstances for the (otherwise) enslaver, rapist, robber, and murderer to commit those acts upon that person given the otherwise-victim's nature which desired and found pleasure and satisfaction in them."
If such a person existed, it would mean, to me, such a person is crazy as a shithouse rat.
Thing is: there are plenty of crazy folks in the world and many -- particularly those obsessed with a fetish -- often enjoy bein' submissive and bein' humiliated. But even these poor, sick bastards still lay claim to themselves.
What I'm sayin': morality (what is permissible between and among men) isn't, can't be, mutable. Nor can there be multiple strains of morality. What apples to one, if we're talkin' about moral fact, must apply to all, or it's just moral opinion.
"Thanks for your thoughts."
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Mannie pondered: "From where, then, comes any inclination to choose evil, if not from some harkening in the nature of the chooser?"
As I say: evil is a free will preying on another free will. That is, a person chooses to ignore another's right to his own life, liberty, and property, treating him as a commodity. He self-corrupts, is corruptible, but it does it doesn't follow he is innately corrupted. If he were adulterated from the start, that, it seems to me, short circuits his status as a free will. This harkening, then, is not his evil nature.
You ask, 'why, if he understands the choice is wrong, does he choose to it?' I admit: congenital corruption is a good answer...it just doesn't sit right with me. The 'evil nature', as I say, precludes, or seems to preclude, one's status as a free will. It smells of determinism.
Frankly, I find it easier to accept the idea of Screwtape's nephew, who sits on a shoulder whisperin' in an ear, than a congenital stain.
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iam, with incredulity, (rhetorically) asked: "So, with a straight face, henry is going to tell us that his best buddy IC has not made every effort to bring him over to accepting Jesus Christ as his personal savior?!!"
I can't say if Mannie gave it his best shot. Only he can say. I tell you this, though (for what it's worth): when we talk to each other, we actually talk 'to' each other. Our conversations are not exercises in one-upmanship. We don't agree on many things. We always, however, respect one another and are, therefore, respectful 'to' one another. I believe Mannie is an honorable man; I'd like to , believe he thinks the same of me.
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iam asked (rhetorically): "What's the skinny here with you and IC and Jesus Christ?"
I've defined my relationship with Mannie just above. I have nuthin' more to say on it, to you or anyone. As for Jesus and Mannie: talk to Mannie. As for Jesus and me: I have a great deal of respect for the man as he appears in The Jefferson Bible.
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iam (rhetorically) asserted: "Anyone who truly did believe they had demonstrable evidence that a God, the God, their God did in fact exist would do everything in their power to spread the news."
Why? I, for example, believe it is possible to demonstrate (the possibility of) God's existence. I've offered what I see as the chief evidences, multiple times, in-forum. But, I certainly haven't done 'everything in my power to spread the news'. Why should I?