Arghh, I've been asked out on a semi-date 
and now I'm thinking I wish I hadn't accepted. I don't have those feelings for him. It was never (in my mind) meant to lead to dating. We met through having the same strong professional interests & I made the first move asking if he'd like to meet for coffee/chat as I was fascinated by his work - we work in similar areas of research. We have mutual 'colleagues' in common & our paths may cross again and again in the future. Well that first chat lead to dinner which was okay but I politely kept my boundaries when an intimate moment presented itself. Officially, nothing has happened but there's definately this undercurrent now of dating and I feel uncomfortable. He's too old for me & I'm not interested in him that way. In fact he's not the person I thought he was at all. He's only ever been polite though and there's been no funny business but there have been a couple of hugs. How do I gently break this without any awkwardnes? I've kind of fallen in to something like dating & that was never my intention. Our paths are likely to cross again and again in the future through work. Neither of us has actually mentioned a date so it feels uncomfortable saying 'I don't want to date you' when officially, it was never that to start with! Help me! I just want to be nice to the guy without either of us losing face.
For the record, we are both single.