[gus_massa]

>> * Every thing that happens, happens at a time.

What is a "time"? Is it a number? A string like "uyeuhwydyjghafjhbhsjahsgg"? Some opaque object? Is it possible to compre the "time" of two different events? If there are two different events, did they happen at the same "time" or at different "time"?

[vintermann]

Come on! I make a serious effort to be precise here, and you just don't seem to give a damn.

Time is a word, and I'm trying to establish the absolute minimum common sense rules for using that word. Obviously we have to use other words to do that, words like "event", "cause" and "order" (note, not "object"). But that's OK, the point is to explain what we mean by these words in relation to each other.

To answer your questions explicitly:

* Time, in this philosophical, pre-experimental sense, is not a number. It does not have anything like a unit or scale. It's certainly not a gobbeldygook string.

* You can only order the time of two events, and only if one is in the set of causes of the other (or the causes of causes etc. Talking about an ordering implies that, I hope you agree.) If an event A has two causes B and C, all we can say for sure is that the times of B and C are ordered before the time of A, because that's what we mean by these words, time, cause and event.

* No, you can never say for sure that something happened at the same time. You can maybe order the times, if they are in a causal chain - in that case it makes no sense to say they're equal. If they are not in a causal chain with each other, you can say nothing about their order (or equality). We know nothing about the order of B and C.

[gus_massa]

So the idea is to assign a different "time" to each event. It's very different from physics, because physics assigns the "same" time to multiple events.

In Newtonian Mechanics, everyone agree to assign the same time to the same collection of events.

In Special Relativity, the same time is assigned to different collections of events by different observers.

In General Relativity, it's more complicated.

Back to your original comment

>>> *Every event happens in a place.

Does each event get a different place, of places can be shared between events?

[tsimionescu]

The t coordinate of 4D Minkowski space-time perfectly corresponds with the definition that the GP was making. As does the t in Newtonian mechanics.

> Does each event get a different place, of places can be shared between events?

Why is this even a question? It is obvious from the definition that two events can happen at the same place at different times.

The theory instead (wisely) says nothing about events happening at the same time.

[gus_massa]

I agree. In Classic Mechanic "time" an be just t (or an opaque container with t), but in Special Relativity you "time" as defined by the G...P must be (t,x,y,z) (or an opaque container with (t,x,y,z)).

> Why is this even a question?

It's very strange that two events can not share the same "time". This is not the usual definition of time in physics [1]. So it's a natural question if the same strange property apply to "place".

Also, the definition of "time" in a world with special relativity makes it necessary to include (x,y,z) so "time" includes all the information included in "place". Why is it necessary to have both concepts?

[1] I think it gets more complicated in General Relativity, but I never took that course :( .