The loose flank is a better clue than a wagging tail. On a rug, a puppy may lie with hips tipped sideways, paws uncurled, jaw soft, and breathing even; yet its eyes track a shoe, a hand, or the faint scrape beyond a door. Rest is not surrender.
That contrast deserves less romantic reading. Loose muscles and an unguarded mouth can reflect a settled autonomic nervous system, while head turns, ear movements, and brief gaze shifts belong to the orienting response, the brain's allocation of attention toward possible information. Calm can still compute. Tail carriage matters, but it is poor evidence alone; a wag can accompany greeting, uncertainty, or arousal, which is why skilled handlers read clusters of signals rather than a single gesture.
The mistake is treating stillness as a verdict. Context decides the signal: a low, pliant body with normal breathing and easy movement differs from one held rigid, lips tense, pupils widened, or escape routes repeatedly checked. Watch the whole animal. In that small pause, repose and inquiry share the same pair of eyes.