On a different thread concerning the likely employment of wizards, it was suggested (more than once) that one role a wizard might play is to detect lies. This could be invaluable to a ruler.
I'd like to propose a contra, just to see how it plays out.
Contra: lie detection is not reliable for monarchs.
Item: the Detector (one who can magically detect lies) might say the Questioned (the one who might be lying) speaks true, and this itself might be true. But the Questioned might in fact simply be ill informed. The Questioned might say So-and-so intends to invade, but the Questioned has himself been lied to. He speaks truth as far as he knows, the Detector detects truth, yet the monarch is misled.
Item: the converse. The Detector might say, the Question lies, and this may be so. Yet the Questioned, being himself deceived, unwittingly says a thing that turns out to be true. Or, the Questioned might indeed be lying intentionally, yet is nevertheless mistaken, and the converse turns out to be true. Either way, the monarch is deceived.
Item: the truth may be insufficient. The Detector detects truth or falsehood, but the information as stated is, unknown to the Questioned, incomplete. A partial truth, or partial lie, can be more misleading than an outright lie.
Item: Even a Detector can lie. The Detector might be a secret agent, working for a rival power. Or might have been recently suborned. Either way, the monarch has no way of knowing whether any single statement by the Detector is itself true or false. It is a case of who guards the guardians.
Item: If magic can detect truth, there must surely be a spell that can counteract this, thus deceiving the Detector. The monarch has no way to know whether or not this has happened.
Ergo: most monarchs, being by nature confident and in command, are more likely to rely on their own natural judgment of other beings. Their ability to read voice and face would be supplemented by the torturer's skills. A Detector might be more trouble than they're worth.
Postscriptum: it would be interesting to add the ability to detect lies in other forms. For example, whether a lie is contained in writing. Or whether someone approaching is doing so with honest intent. And for another wrinkle, the ability to detect lies could vary across types--elves, humans, dwarves, etc. Or vary by circumstance or any of a dozen other variables. The above considerations would still apply, though.
I'd like to propose a contra, just to see how it plays out.
Contra: lie detection is not reliable for monarchs.
Item: the Detector (one who can magically detect lies) might say the Questioned (the one who might be lying) speaks true, and this itself might be true. But the Questioned might in fact simply be ill informed. The Questioned might say So-and-so intends to invade, but the Questioned has himself been lied to. He speaks truth as far as he knows, the Detector detects truth, yet the monarch is misled.
Item: the converse. The Detector might say, the Question lies, and this may be so. Yet the Questioned, being himself deceived, unwittingly says a thing that turns out to be true. Or, the Questioned might indeed be lying intentionally, yet is nevertheless mistaken, and the converse turns out to be true. Either way, the monarch is deceived.
Item: the truth may be insufficient. The Detector detects truth or falsehood, but the information as stated is, unknown to the Questioned, incomplete. A partial truth, or partial lie, can be more misleading than an outright lie.
Item: Even a Detector can lie. The Detector might be a secret agent, working for a rival power. Or might have been recently suborned. Either way, the monarch has no way of knowing whether any single statement by the Detector is itself true or false. It is a case of who guards the guardians.
Item: If magic can detect truth, there must surely be a spell that can counteract this, thus deceiving the Detector. The monarch has no way to know whether or not this has happened.
Ergo: most monarchs, being by nature confident and in command, are more likely to rely on their own natural judgment of other beings. Their ability to read voice and face would be supplemented by the torturer's skills. A Detector might be more trouble than they're worth.
Postscriptum: it would be interesting to add the ability to detect lies in other forms. For example, whether a lie is contained in writing. Or whether someone approaching is doing so with honest intent. And for another wrinkle, the ability to detect lies could vary across types--elves, humans, dwarves, etc. Or vary by circumstance or any of a dozen other variables. The above considerations would still apply, though.