When am I Drinking Coffee?

Or, why time is a logical contradiction according to philosopher James McTaggart

When Am I Drinking Coffee? 

In probably the most famous thought experiment about time, philosopher James McTaggart presents us with his A Series and B Series of Time, shows that these are the only two possible ways of considering time, and since each is logically impossible, that time itself must be a mirage. 

It’s easier for me to consider each series in reverse, B first. The B Series states that time/events can either occur before or after each other, as in earlier or later. Makes sense so far. Time is a series of steps. Earlier my coffee cup was full and piping hot. Later it is (or was), sadly, it’s empty. 

Unfortunately Earlier and Later are good at relative positioning but not moving from past to present or future. Both earlier and later could be “past” or they could both be steps in a checklist for the future. They are a succession without an anchor. 

The A Series is more robust in a way: it states that time/events can be labeled as past, present or future. This aligned with our intuition. Right now, in the past, my coffee cup was full, in the present it’s half full/empty, and in the future it will be empty. So far so good in the coffee-drinking world. 

Unfortunately this description becomes a death spiral and causes mental gymnastic when we try to fix each event in one and only one time bucket forever: in the current present the “event” of my drinking coffee cup was in the past. 

But that same coffee cup was also full in that present - in the past, at the moment of the pour event. From the perspective of the coffee-drinking event the cup is (still) full. And from the viewpoint of that event it always will be.  

Word tenses quickly become circular without one time being fixed to provide relative designations. In the future my empty coffee cup will be “present,” it won’t be the “future” that it is now. 

Apparently we need a fixed point outside of time or words - or deeply inside time, to compare with past, present and future. Otherwise time designations are turtles all the way down. From a descriptive standpoint they all “exist” right now. In the past my coffee cup was full in the present….

If time is either described as Past/Present/Future then it’s entirely relative. If time is Before and After then it has no mechanism to transition from then to now. Time requires all those attributes to function but the foundations still collapse under definitions. Therefore, McTaggart said, time is a contradiction, and logically proving a contradiction is the death knell of a philosophical concept.