When we dream , we often "time-jump" (for want of a better word). Things that were, blend in with things that are, and in our dream mind, it is perfectly fine. As an example, last night I was dreaming about a time when my oldest son (now 51) was still a teenager; but in that dream, I had a cell phone, and it was perfectly fine in my dream mind. After I woke up, I was thinking about this, and that our dreams come from our subconscious mind. Therefore, it would seem that time ONLY exists in the conscious mind, because the sub-conscious can happily mix up events from the present and the past, and not give it a moment of confusion about doing that. This caused me to ask myself whether time itself is real, or just an illusion that helps us to understand our world better. Thoughts ?