Obviously, infinite speeds would defeat time keeping. Infinite speed would imply that a particle could be at the same time at the start point of its trajectory and at the same time at the end point of it. At the least, we should not call that a particle anymore, if it is able to be at two positions at the same time. But if we are able to observe this entity as being a particle, then we should be able to distinguish the two positions with our clocks. Then, we should simply improve the way we build (or chose) our clocks, Since clock is the empirical way to define time, we can only conclude that infinite speeds are impossible, by principle. This brings me to my question: Could that point of view be sufficient to build the special theory of relativity? Could that point of view imply some limit speed for particles?