Does a petrified creature stay conscious (and sane)?

Question

The next dungeon my party visits will contain some strange statues. Most of them are just Stone Golems, which will attack them. But near the end of the dungeon, the party will discover that one of the statues is no statue at all, but a petrified monk. He was petrified over 500 years ago (which is important for plot reasons) by a flesh to stone spell. The party cleric will (probably) cast greater restoration and turn the monk back to normal. I really like this idea, because it allows me to bring in an eyewitness who experienced firsthand what happened half a millennium ago.

I assumed that the monk would be thankful and glad to share some reliable knowledge with the party. Then I read through the petrified condition:

• A petrified creature is transformed, along with any nonmagical object it is wearing or carrying, into a solid inanimate substance (usually stone). Its weight increases by a factor of ten, and it ceases aging.
• The creature is incapacitated (see the condition), can’t move or speak, and is unaware of its surroundings.
• Attack rolls against the creature have advantage.
• The creature automatically fails Strength and Dexterity saving throws.
• The creature has resistance to all damage.
• The creature is immune to poison and disease, although a poison or disease already in its system is suspended, not neutralized.

A petrified creature is also incapacitated:

• An incapacitated creature can’t take actions or reactions.

But I cannot find the part where it says that the petrified creature is unconscious. Which means that this poor monk stood in the dungeon for 500 years without being able to see, hear or feel anything. Completely alone with his thoughts. As a consequence, he is probably insane after the cleric fixed him. Am I overlooking something?

Does a petrified creature stay conscious (and mentally sane)?

Answer 1

Not-Unconscious does not necessarily mean awake and aware.

Sometimes the game just expects us to understand certain terms without giving explicit rules text about what they mean. Famously, 5e doesn't specify a 'dead' condition or give any rules about what it means to be dead. So there is a precedent for the game having certain game concepts left to the players' understanding of the world without giving specific rules text.

The Unconscious condition has specific effects that don't jibe with petrification: Unconscious creatures fall prone, drop their belongings, and take automatic critical hits, none of which makes a lot of sense with a creature being turned to stone. So there's a good reason not to bring those into a petrification situation.

Which is a all a rather long way to say 'the DM decides that', but:

What rules text even represents being mentally shut down?

Other than the actual name of the condition, the "incapacitated, can't move or speak, and unaware of surroundings" bullet point is as close as the Unconscious condition ever gets to specifying that your mind is shut off, and that text is present in Petrified as well.

So, for whatever it's worth, it seems like Petrified includes the mental component of unconsciousness, in so far as that state is represented in rules text at all.

Answer 2

Remains Sane and Conscious*

tl;dr The petrified monk is not unconscious, and remains sane as the duration of petrification passes quickly from their point of view.

This is About Narrative

Since the effects of the spell do not indicate the long term narrative effects, it is left up to the GM to fill in. The following is a narrative explanation supported by an interpretation of the mechanical description that supports a sane monk after being petrified.

Conscious

The spell does not indicate that the target becomes unconscious, so it does not become unconscious.

Passage of Time not Observed

While the petrified creature is not unconscious, it is not specified that it observes the passage of time in the same way as the rest of the non-petrified world. The conditions taken together seem to indicate that the petrified monk will not be observing the passage of time in the same way as the rest of the world.

• ceases aging

• The creature is incapacitated (see the condition), can’t move or speak, and is unaware of its surroundings.

• a poison or disease already in its system is suspended

The monk would have no way of knowing how long they were petrified. There is no wall clock, and the conditions above indicate a suspension of animation.

Sanity Preserved

Petrification Duration is Different from Perspective of Monk

500 years passes in the blink of an eye for the petrified monk. From their point of view, very little time has passed.

Insanity as a Disease

If you consider insanity to be a disease of the mind, then the spell text specifically forbids that.

The creature is immune to poison and disease

Answer 3

It seems that the first bullet point is the one that answers your question:

A petrified creature is transformed, along with any nonmagical object it is wearing or carrying, into a solid inanimate substance (usually stone). Its weight increases by a factor of ten, and it ceases aging.

The highlighted section means that the result is not living. It has become a solid non-living statue. The remaining bullet points are mostly just reinforcing the rules you should use for the statue, and saying that reversing the condition will restore it in a condition that includes any poisons or diseases it was suffering before the initial transformation.

While no mention is made about mental saving throws it seems clear that this is due to the fact that a statue has no mind to affect.

It could be argued that the target's soul remains bound to the physical object and could be affected by anything that specifically targets souls, but while so bound it is unlikely that it would continue to process anything like conscious thought.

And since there is no mind it is trivially true that the target cannot go insane. Depending on how long it takes to fully petrify and to revert the petrification the target may never even have an awful experience to unbalance their minds after revival. They might wonder what happened to the world and why they're suddenly covered in all this dust, but if the transformations were practically instantaneous it would be like blinking and finding the world had changed around you.

All of the above assumes that memories and thoughts are something done by the brain during corporeal existence and that only souls that have been separated from their bodies - by death, astral projection, etc - are capable of thinking without a functional brain. Since you can render somebody unconscious by purely physical means it seems reasonable to assume that this is the case.