Traditional institutions are often considered inadequate to govern for the long term as their politicians promote short-term thinking which can harm the future. This book proposes a novel theory of social time perception to address the short-term thinking of traditional institutions which threaten to stifle liberal democracies. The semi-future reconfigures liberal democracies' franchises, representative instruments, deliberative practices, accountability mechanisms, and policymaking to include in the demos all citizens, regardless of age, and holders of representable objective interests in the future. The result is not only a way to legitimise long-term governance but also to improve the quality of current democracies.