Two pleasures — the rising edge (来劲) and the falling edge (过瘾)
An illustrative-formula dissection of engagement: mathematical notation used not to measure but to fix a relationship (a derivative, an edge) so it becomes operational. Built by stripping the folk words down to function.
The five-concept system
- 刺激 (stimulus / spike) — a local, sudden deviation from baseline in the information field (physical jolt, meaning-salience, or prediction error). Instantaneous; depends on change量, not duration. (Grounded: Sokolov's orienting response; Friston predictive-coding surprisal.)
- 体验 (experience / integration) — multimodal information integrated over time into a bounded event-model; depends on duration + structural completeness + an ending. (Grounded: episodic-memory sequence binding; Bruner narrative psychology.)
- 能量 (energy) — the rate of state-transition, not the state level: energy ≈ d(state)/dt across arousal / attention / valence / load. Illustrative use of the derivative — the payload is "what's felt is the change, not the level."
- 来劲 (onset-arousal) = the RISING edge — a stimulus is gated by meaning ("worth投入") → neural energy jumps 0→1 → attention/participation surge. Reward-anticipation (Berridge "wanting"). Present/future tense. This is the hook primitive (delivery-craft P4, video hook rules).
- 过瘾 (closure-satisfaction) = the FALLING edge — after a complete experience the input drops to zero, neural energy falls 1→0 by inertia, and consciousness captures the residue of the peak-to-baseline drop. Reward-realization (Berridge "liking"). Past tense. The payoff / peak-end primitive.
The formula that carries the insight
来劲 = 感知到的能量上升沿 (0 → 1, the jump)
过瘾 = 感知到的能量下降沿的余韵 (1 → 0, the fall's afterglow)
Neither symbol is measurable; the form is the point — one is a rising edge, one a falling edge of the same energy curve. It follows immediately that 过瘾 requires the energy to have first been pulled high (no high-intensity build → no afterglow on the drop), and that they can dissociate: rapid-cut short-video reels give constant 来劲 (spikes) but no 过瘾 (no complete arc to close) → the felt emptiness after doom-scrolling.
The correction that matters (the owner's cut)
过瘾 does not require a pre-existing appetite ("瘾"). Nobody enters a film with a need to sate, yet a good film is 过瘾 — because the experience manufactures its own expectation in real time and then closes it. Etymology (过+瘾 → "satisfying an addiction") actively misleads; define by function. This is exactly tension-and-release / setup→punchline: the artifact creates the debt, then pays it.
Epistemic honesty (from the dialogue's own self-audit)
The grounded layer (orienting response, predictive coding, wanting/liking dissociation, dynamical-systems "energy as state-transition rate") is real cognitive science; the unification into one five-concept chain and the rising/falling-edge mapping is a recombination built for this purpose — an explanatory model, not a discovered law. That honest split is itself the right posture for the whole illustrative-formula genre: the science grounds the terms, the equation-form is a chosen lens.
The engagement contract
Trigger 来劲 fast (hook — anticipation, or they scroll) AND deliver 过瘾 at the end (payoff — realization, or they feel cheated and don't return); retention is the bridge that keeps the manufactured tension alive between the two edges.
Kin: illustrative-formulas (the genre this exemplifies) · tension-and-release · peak-end (video-craft P3) · zeigarnik-effect (the open loop = the debt) · desire-is-labor (who manufactures the wanting) · delivery-craft P4 (hook) = 来劲-engineering.