Question

Hans Reichenbach argues for the causality and causal chain to define a topological coordinative definition of time order. Here is an excerpt from his textbook, The Philosophy of Space and Time, Dover(1957), pp.138

Another example: We throw a stone from A to B. If we mark the stone with a piece of chalk at A, it will carry the same mark when it strives at B (event E2). If we mark the stone only on its arrival at B, then the stone leaving A (event E1) has no mark.

This distinction appears trivial, but it is extremely significant. A theory of causality which ignores this elementary difference has neglected the most essential aspect. The procedure which we have described is used constantly in everyday life to establish a time order, and we have no other method in many scientific investigations where time intervals are too short to be directly observable. We must therefore include the mark principle in the foundations of the theory of time.

We have in the above principle a criterion for causal order that does not employ the direction of time, and we can therefore use it in our definition of time order. There exists a topological coordinative definition for time order. We can base it in general on the concept of the causal chain, in which the order of events corresponds to the order of time. Occasionally one speaks also of signals or signal chains. It should be noted that the word "signal" means the transmission of signs and hence concerns the very principle of causal order which we have discussed.

My issue is, isn't he implicitly assuming prior and later time, i.e, the time order in defining the causal events? Isn't the mark principle takes into account the time ordering? How is this decoupled from the time ordering?

Answer 1

Hans Reichenbach argues for a topological coordinative definition of time order based on the mark principle, which does not explicitly assume prior and later time. The mark principle states that if we mark a stone before it leaves point A, it will still carry the mark when it arrives at point B.

Step-by-step explanation:

Hans Reichenbach argues for the causal chain to define a topological coordinative definition of time order. The mark principle he mentions is a criterion for causal order that does not directly employ the concept of time. It is based on the observation that if we mark a stone before it leaves point A, it will still carry the mark when it arrives at point B. Reichenbach's argument is that this principle can be used as a basis for defining time order, without explicitly assuming prior and later time.