>>Three worms going in a line.
>>
>>1st worm says "there are two worms behind me"
>>
>>2nd worm says "there is a worm ahead of me and a worm behind me"
>>
>>3rd worm says "there is a worm ahead of me and a worm behind me"
>>
>>How is this possible?
>
>They are talking about different things when saying "behind". Two of them are talking about being "physically" behind and one is talking about being behind time-wise, as they started at different point in time.
Spacial meaning only - but by now you know the answer.