Plotinus's epistrophē: all things yearn to return to the Source. Given only what emanated — the outputs — can you climb back to the One that made them? The posterior sharpens with every observation, but never closes to a point. The return is real, and never complete.
The Source is a hidden coin θ; each emanation is a Bernoulli(θ) draw. Starting from a uniform prior, the posterior is the exact conjugate Beta(1+heads, 1+tails); its mean and standard deviation are computed exactly and drawn live, alongside a Gaussian approximation to its differential entropy. With more data the posterior narrows around the true θ — but its std shrinks only as ~1/√N (never to 0) and the approximate entropy trends down without ever reaching −∞: you approach the Source, you never stand on it.
'Yearning to return', 'the One that made them' — Plotinus's figure of epistrophē. The mechanism is ordinary Bayesian inference: a posterior over a parameter given observations. The 'Source' is a coin we set; the instrument recovers a number, not a soul.
Even perfect inference returns only a distribution, never the thing itself — and it is only as right as the model. If the outputs did not actually come from a coin, a confident narrow posterior would be confidently wrong. The return reaches the best estimate the model allows, and no further.