The dragon is just a gauge. Gauge symmetry

>If someone claims to have a dragon that is invisible, silent, intangible, and undetectable by any means, there is no practical difference between the dragon’s existence and non-existence.

“Everyone knows that dragons don’t exist. But while this simplistic formulation may satisfy the layman, it does not suffice for the scientific mind. The School of Higher Neantical Nillity is in fact wholly unconcerned with what does exist. Indeed, the banality of existence has been so amply demonstrated, there is no need for us to discuss it any further here. The brilliant Cerebron, attacking the problem analytically, discovered three distinct kinds of dragon: the mythical, the chimerical, and the purely hypothetical. They were all, one might say, nonexistent, but each non-existed in an entirely different way.” ― Stanisław Lem, The Cyberiad

> If someone claims to have a dragon that is invisible, silent, intangible, and undetectable by any means, there is no practical difference between the dragon’s existence and non-existence.

Unsurprising that the longest subthread here is one criticizing the premise.

Doesn’t silent, invisible, intangible also apply to software?

You can’t really tell a particular piece of hardware is running software by a direct physical measurement. You can only infer that indirectly.

The dragon in the room is the hidden qualifier for "undetectable by any means" is "that is currently known to humanity".

That makes Carl Sagan's claim some what Balonish. Not sure why the smart Sagan fell for it.

A parking lot dragon? This sounds familiar. [Assuming not a Dragon of Eden, nor one who farts nerve gas] I believe it is a parable about cause and effect; consistency of the world's state.

A parking garage, poured in modern times from reinforced concrete, might have been found to be structurally unstable during a renovation. If this turned out to be rooted in a massive [dragon, dinosaur, etc] skeleton being embedded in the concrete (As it was being poured?) surely this would be a contradiction, if people (workers, onlookers) witnessed the garage's construction.

There would be evidence from the reinforcement efforts; materials sourced to reinforce it due to structural flaws introduced by the skeleton; wear on the truck tires carrying them, memories in brains etc. If suddenly the skeleton were to have vanished, would there be logical consistency problems with the world state? Quite a thing to ponder!

I would like to clarify that this is purely a thought experiment. It is not possible that any group of people, no matter how secluded, could either A: Will such a reptile into existence while maintaining cosmological consistency, nor B: Remove it from our cosmos after evidence over its existence has propagated.