What causes us to develop "feelings" for someone

[RainforestLizard]

Just one of my wonderings from today...

What, in your opinion, makes someone develop feelings for someone?

There are loads of lovely people around and many people chat and interact with many different people on a regular basis so what makes someone start to fall for someone else? Why, for example, would Tim fall for Susan when he has the same level of interaction and involvement with both Susan and Helen? I'm aware that physical attraction plays a part, obviously. But what else exactly?

What's your view? Any ideas and thoughts or stories welcome.

I feel very philosophical tonight! No alcohol either...

For me it's often a sense that someone ' gets' me and has a similar personality and similar ways of thinking. I've often been considered odd/weird by other people, so when I meet someone who not only understands my slight eccentricity and off-beat-ness but actually appreciates and shares them, that can be very powerful.

I'd say a mix of the right balance of intellectual, emotional and sexual similarity and attraction.

I think it's because you like their smell. My DP is soooo not my type (or so I thought when we met) but he's great and I think it was mainly his nice clean smell (not soap etc but just general personal smell) that drew me to him.

Isn't it to do with things like pheromones and we subconsciously pick up on things that make a possible mating partner a good genetic match. Underneath were all basically animals looking to procreate with the best match (whether consciously we want children or not).

I also read somewhere once that kissing passes over loads of subconscious info about being a match and that's why you can really like someone and then the kiss is so flat you go off them as they're not suitable for your genetic make up. It's also apparently why men generally like big breasts as they're looking for a strong mate and why women generally like macho men as they are meant to be the hunter providing for the family.

Obviously none of the terms I've used are the best scientific vocabulary to describe it. And it's all just tit bits I've read here and there and concluded myself.

I've read before about smell and pheromones. Which makes sense from an evolutionary point of view. But, I guess the romantic in me means this logical explanation doesn't sit right with me.