Heraclitean Generalization of Special Relativity Joy Christian A generalization of special relativity is constructed in which the inverse of the Planck time takes over the role of observer-independent conversion factor usually played by the speed of light. The latter remains an invariant as much as in special relativity, but now emerges as a derivative quantity. In the fully relativistic theory based on the generalization, energies and momenta turn out to be invariantly bounded from above---and lengths and durations similarly bounded from below---by their respective Planck scale values. The generalized theory abhors any form of a preferred frame of reference, and yet, along the external timelike world-lines, it captures "temporal becoming" as a genuinely structural attribute of the world. Thus indeterminism turns out to be a truly intrinsic feature of the corresponding spatio-temporal sector, independently of any quantum mechanical considerations. This is quite unlike special relativity, which happens to be naturally conducive to a deterministic (i.e., Parmenidean or "block") interpretation. The minute deviations from the special relativistic dispersion relations and Doppler shifts predicted by the generalized theory remain quadratically suppressed by the Planck energy, but may nevertheless be testable in the near future, for example via observations of cosmogenic neutrino oscillations or pulse rates of binary pulsars.