The Duverger Syndrome is democracies' most critical illness. Both the causes and the fixes are known. Solutions must be applied as a matter of priority.
Every incoming government promises change. Under single-choice voting, delivering on that promise means undoing what the previous government built. The previous government had done the same to its predecessor. The next one will do the same in return. This is the Policy Pendulum: the do-undo-redo cycle that single-choice voting makes structurally inevitable.
Political scientists use a French term for the underlying mechanism: alternance, the regular rotation of governing power between two opposing blocs. But naming it is not the same as understanding what makes it so destructive. The disease is the mutual enmity that single-choice voting produces: two blocs defined as irreconcilable enemies, each treating the other's record not as a foundation to build on but as a legacy to demolish. Power changes hands; the work is destroyed; it begins again. The country oscillates. A pendulum does not progress — it swings.
Under Informed Score Voting, the dynamics are entirely different: when leadership changes, the baton is passed — the next coalition continues the work the previous one began rather than reversing it. Policy built on broad cross-party consensus does not carry one side's signature. No incoming coalition inherits an enemy's legacy. It inherits a foundation and adds its own layer. That is what successive governments were supposed to do. Single-choice voting made it impossible. The Policy Pendulum is what replaced it.
The cycle is visible across policy domains and across countries wherever single-choice voting produces a binary:
The pattern across all these cases is the same. The incoming government does not evaluate its predecessor's policies on their merits. It evaluates them by their origin. Policies that originated with the enemy are reversed; policies reversed by the enemy are restored. The do-undo-redo cycle does not require anyone to be especially incompetent or malicious — it is the structural output of a system in which each government's identity is defined by opposition to the last.
Three reinforcing dynamics sustain the pendulum and prevent it from correcting itself:
Zero-sum identity. In a binary system, acknowledging that the previous government got something right is a political gift to the enemy. The incentive is to distinguish rather than to build. Each new government needs its own signature — which means rejecting its predecessor's. Policy continuity is indistinguishable from conceding that the other side was correct.
Base expectations. The party's base did not vote for continuity. It voted for reversal. A government that maintains its predecessor's policies faces the same purity ratchet that Primary Radicalisation applies to individual representatives: the base reads it as surrender, as insufficient commitment to the cause. Continuity is politically dangerous; reversal is the expected proof of loyalty.
Institutional capture by the incoming coalition. Each new government brings its own ideological ecosystem into office — advisors, department heads, commissioners, judicial appointments. These actors have structural incentives to favour the new government's agenda over inherited ones. They are not merely political appointees; they are the infrastructure that makes reversal operationally possible at every level of the executive. The pendulum does not swing only at the top — it propagates through the entire institutional machinery.
The ratchet that enforces this has no internal corrective mechanism. The binary produces the incentive; the incentive produces the reversal; the reversal deepens the binary. Each cycle confirms to each camp that the other's record deserves to be undone, which confirms the original incentive for the next cycle.
The policy domains most critical to long-term human welfare — climate, infrastructure, public health, energy transition, pension systems, education — operate on timescales far longer than electoral cycles. Solving them requires sustained, compounding policy across decades. The Policy Pendulum makes this structurally impossible.
Climate policy is the starkest case. The scientific consensus is not a matter of political dispute, but the policy response requires international agreements, domestic legislation, infrastructure investment, and industrial transformation that must all be maintained across generations. A system in which each election risks reversing the previous government's climate commitments cannot produce the kind of sustained action that the problem requires. The do-undo-redo cycle does not care about the scientific timeline. It only cares about the electoral one.
Infrastructure tells the same story. Deferred maintenance compounds. A bridge not maintained across three administrations of reversal costs more to repair than one maintained consistently. A rail network privatised, partially renationalised, privatised again, and then renationalised under emergency conditions represents not merely political inefficiency but physical deterioration of the underlying asset.
The human cost is less visible but more direct. Patients who qualified for healthcare under one administration and lose it under the next do not experience a policy debate — they experience a loss of coverage. Entrepreneurs who built a business around a tariff structure, a tax incentive, or a regulatory framework cannot plan beyond the next election — because the next election may abolish the framework the business was built on. The oscillation is not abstract to the people who live inside it.
The Policy Pendulum is also the domestic mechanism that creates the strategic vulnerability analysed in Authoritarian Advantage. Democratic states that cannot commit beyond the next election face authoritarian adversaries who can plan on historical timescales. The do-undo-redo cycle is not merely a domestic governance failure — it is the structural condition that patient adversaries have learned to exploit, studied, and built long-term strategies around.
The Policy Pendulum is produced by the binary, and the binary is produced by single-choice voting. The cure is structural.
Under Informed Score Voting, governing coalitions span multiple parties and ideological positions. Policy built on cross-party consensus does not carry one side's signature — it carries the signatures of parties from multiple points of the spectrum. When the next election produces a different coalition, it does not automatically inherit an enemy's legacy. It inherits policy with cross-partisan authorship.
Reversing such policy requires building a new cross-party consensus against it. That is harder — specifically and deliberately harder — than the simple majority that enacts it. Not impossible: genuine policy failures can and should be reversed. But the default is no longer automatic reversal. The incoming government inherits a floor of shared achievement rather than a ruin to demolish.
This is what the shift from single-choice voting to Informed Score Voting ultimately produces at the policy level: a reduction in the rate at which democratic energy is consumed in cyclic reversal, and a corresponding increase in the rate at which it compounds toward long-term progress. The pendulum does not stop. It slows — and when it slows, governments can build on what their predecessors built rather than demolish it. That accumulated building, across decades and policy domains, is the difference between a democracy that perpetually exacerbates its problems and one that finally resolves them.