It's amazing how many lies go undetected because people simply don't care. I can't tell a lie to fool God, but I can certainly achieve my aims by telling even blatant, obvious lies to human beings, who rarely bother trying to sort out the lies and when they do aren't very good at it.

It sounds to me like you're overreaching for a pragmatic reason not to lie, when you either need to admit that honesty is an end in itself or admit that lies are useful.

Honesty is an end in itself, but because the benefits involve unknown unknowns and black-swan bets, they are underrated.

I agree with Nominull, a good number of lies are undetectable without having access to some sort of lie detector or the agent's source code. If an AI wanted to lie "my recursive modification of my goal systems hasn't led me to accept a goal that involves eventually destroying all human life" I don't see any way we could bust that lie via the 'Web' until the AI was actively pursuing that goal. I value honesty not for the trouble it saves me but because I find (sometimes only hope) that the real world free of distortion is more interesting than any misrepresentation humans can conjure for selfish means.

@"Oh what a tangled web we weave, when first we practise to deceive," said Shakespeare.

Hopefully, the FAI will know that the author was Sir Walter Scott.

"Human beings, who are not gods, often fail to imagine all the facts they would need to distort to tell a truly plausible lie."

One of my pet hobbies is constructing metaphors for reality which are blatantly, factually wrong, but which share enough of the deep structure of reality to be internally consistent. Suppose that you have good evidence for facts A, B, and C. If you think about A, B, and C, you can deduce facts D, E, F, and so forth. But given how tangled reality is, it's effectively impossible to come up with a complete list of humanly-deducible facts in advance; there's always going to be some fact, Q, which you just didn't think of. Hence, if you map A, B, and C to A', B', and C', use A', B', and C' to deduce Q', and map Q' back to Q, how accurate Q is is a good check for how well you understand A, B, and C.

If a lie is defined as the avoidance of truthfully satisfying interrogative sentences (this includes remaining silent), then it wouldn't be honest, under request, to withhold details of a referent. But privacy depends on the existence of some unireferents, as opposed to none and to coreferents. If all privacy shouldn't be abolished, then it isn't clear that the benefits of honesty as an end in itself are underrated.

"[...] when I talk about the Great Web of Causality. I use these Capitalized Letters somewhat tongue-in-cheek [...]"

Personally, I prefer "Great Romance of Determinism."

"Other planets in space and time, other Everett branches, would generate the same pebble."

But not very likely! At least some of them not. What tells you something abut the Multiverse, if you buy it's idea.

A new method of 'lie detection' is being perfected using functional near infrared imaging of the prefrontal cortex:

http://www.biomed.drexel.edu/fNIR/Contents/deception/

In this technique the device actually measures whether or not a certain memory is being recalled or is being generated on the spot. For example, if you are interrogating a criminal who denies ever being at a crime scene, and you show them a picture of the scene, you can deduce whether he/she has actually seen it or not by measuring if their brain is recalling some sensory data from memory or newly creating and storing it.

@Retired: Huh, I thought I checked that, but I guess I only checked the text instead of the attribution. Fixed.

Tom, I can't visualize your technique: example?

It seems doubtful to me that a pebble includes in it the law of gravity in the sense of determining it. The internal structure of the pebble, the reason it stays solid, locations of its atoms in relation to each other, are all due to electromagnetism (and strong/weak interactions inside the nucleus). Gravity is completely dominated by other forces, to such a degree that it seems plausible to me that an essentially indistinguishable pebble could exist in a universe with a very different gravity law (although in absence of planets it might be more difficult to explain its formation).

@Nominull: "I can certainly achieve my aims by telling even blatant, obvious lies to human beings"

You are leaving digital crumb trails that the technology of the present day can follow and the technology of 20 years hence will be able to fluidly integrate into a universal public panopticon / rewind button. I don't personally bank on keeping any secret at all in that sort of time-frame.

It is in any case a good general heuristic to never do anything that people would still be upset about twenty years later.

So a single pebble probably does not imply our whole Earth. But a single pebble implies a very great deal. From the study of that single pebble you could see the laws of physics and all they imply. Thinking about those laws of physics, you can see that planets will form, and you can guess that the pebble came from such a planet. The internal crystals and molecular formations of the pebble formed under gravity, which tells you something about the planet's mass; the mix of elements in the pebble tells you something about the planet's formation.

Call me sceptical about this. We can deduce a lot from a pebble ourselves because we know a lot about our universe, and about our earth.

But are you sure that there are no exotic laws of physics, across all possible universes, that would give rise to the same structure? Or, more simply, with the powers of a god, could you not lie - change the laws of physics and the structure of the universe, until you produce exactly the same pebble in completely different circumstances?

Oh what a tangled web we weave when first we practice to deceive But- practice makes perfect. Soon, fair youth, Your lies will seem as pure as truth.

I thought quite hard before I came up with an answer to Sir Walter which rhymed and scanned. The hero of that poem, whose name I cannot remember at the moment, is fair haired. Perhaps it is not also true, but perhaps that is the point.

Gravity is completely dominated by other forces, to such a degree that it seems plausible to me that an essentially indistinguishable pebble could exist in a universe with a very different gravity law

Doesn't this depend heavily upon the sensitivity and discrimination of our observing phenomena, as well as whether we examine the pebble as a static, frozen moment or as a phenomenon occurring in time?

For the pebble to truly be completely identical, you might need for it to be embedded in a completely identical cosmos. How small does the difference have to be before it distinguishes one from the other, and do the effects of any one thing on the rest of the cosmos (and vice versa) ever drop to nothing?

No gravity - matter wouldn't have coalesced. It wouldn't have become stars, or fused or been caught up in supernovas, and so a pebble would be an unrealized theoretical possibility.

Caledonian, quantum mechanics may limit the sensitivity and discrimination of our observations. Also, if gravity's so weak on the atomic level in the pebble that its effects would cause a shift in the arrangement of the atoms smaller than the Planck length, it's not even clear that such a shift exists at all, or what meaning it has.

Julian, I suggested that a very different gravity law might be compatible with the existence of a pebble, not no gravity at all.

In fact, all kinds of things might be different about the laws of physics and the pebble could still exist. E.g. the second Newton's law could be wrong (look up MOND), which would change the story on galaxies in a big way, but not affect the pebble at all.

It seems plausible that a small familiar object like a pebble already has all the fundamental physical laws baked into it, so to speak, and that these laws could be deduced from its structure. But it isn't true. It's easy to overestimate how entangled the tangled web is, too.

Nothing is lost; the universe is honest, Time, like the sea, gives all back in the end, But only in its own way, on its own conditions: Empires as grains of sand, forests as coal, Mountains as pebbles. Be still, be still, I say; You were never the water, only a wave; Not substance, but a form substance assumed.

- Elder Olson, 1968

FLOWER in the crannied wall, I pluck you out of the crannies;— Hold you here, root and all, in my hand, Little flower—but if I could understand What you are, root and all, and all in all, 5 I should know what God and man is.

I dare not confess that, lest I should compare with him in excellence; but, to know a man well, were to know himself.