What should I do about this date?

Hello dear TSRians - first warning, if you are TL;DR type person, and don't want to read a mammoth essay, the summary is: "How could you politely postpone a date for 2-3 weeks?" :p For those of you who are bored and fancy a read, I will invest in the best grammar possible to make it an enjoyable read if you do decide to proceed. Anyway, to set the scene, I have a moral clash and I am not sure what to do. Several months ago, I went out with Alex for a brief period of time. I was very taken by him, and we had a fairly intense relationship. However, we called the relationship a day as he was due to spend 8 months abroad. There were no promises for waiting for each other, though there was a certain agreement that we could see each other again when he was finally back (in a very non comittal sense). Since then, I have had a number of short, mild, physical encounters. Initially my feelings for him remained quite strong, although over time I have managed to make them wane a bit and start looking out for other people. To this date, we have contacted each other a very scarce number of times. A couple of days ago, he contacted me saying that he would be coming home in 10 days time for a short period, and was wondering if I would be available at the time. Obviously, my buried interest in him has flourished again - though I am also keeping a fairly skeptical mind about the situation, and don't want to raise my hopes too high as I understand he may no longer feel as strongly about me, or it could end up in a similar "be-with-me-while-he's-here-and-dump-before-leaving-again" situation. Coincidentally, two days ago, I was approached by Ben, whom I had seen previously around campus. We had a very fruitful conversation, in which amongst other things he learnt that I was going home on holiday for Easter shortly. He asked me out to lunch in campus the following day, and whereas I could tell there was probably a romantic intention to it, I accepted (we did not know each other that well and he seemed like a decent person that I would like to get to know better, and a lunch on campus surrounded by people you both know is not quite the epitome of dateness). Although the lunch was not date-y, I can definitely tell that he has some sort of crush on me, and I also think that he is indeed a sweet guy. Anyway, he has now asked if I would like to go out to the movies with him tomorrow - and here is where my brain gets lost: I feel that this would be going a bit too fast. Additionally, if I am totally honest, I would prefer to see how things go with Alex first. If Alex and I are on the same page, I would like to pursue things with him. If Alex does not reciprocate my feelings, I feel I could get some closure and move on. If I get closure and move on, I would like to get to know Ben better, as he does seem like a genuine guy (and I don't want to date 'multiple guys at once' at it seems like a dishonest thing to do). Similarly, this approach may seem like seeing him as "second best", but then again, I used to go out with Alex, and I am only starting to meet Ben - so I would be getting to know him better and hopefully taking it further if you know, we're compatible. So, ideally, I would like to postpone this date 2-3 weeks, without stringing him on or being mean either. As we have only known each other 2 days, he can't be particularly emotionally invested, but anyway, what would you guys do in such a situation? Thanks for reading. :-)

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