In modern mythologies I'm noticing increasing reference to objects/substances that can tell or discern truth. Most famously, the use of truth serum as a trope in the spy genre in particular, and Wonder Woman's miraculous golden cord, newly rebranded as the Lariat of Hestia. The alethiometer (aka the golden compass) from Phillip Pullman's heavily mythological His Dark Materials is a more recent example.
Are there canonical precedents for this power of truth?
Pullman's alethiometer is clearly an oracle, but it is also a device, almost certainly modeled partly on the antikythera mechanism, so it can be understood as distinct from a oracular entity in that the possessor controls the device.
