Think about time, think about the past and the future. Are they real?
Why do we treat the past and future so differently? Why are we thinking of them in such a different way than we think of the different parts of space?
But this a question where as soon as you start thinking about it you begin to suspect that the answer is just this is not a good question to ask.
Time is another dimension in the universe; we can marry the three dimensions of space to the one dimension of time to get four-dimensional spacetime.
