Have you ever thought why romantic atmosphere is so relaxing and often leads to the put-up result?;)
It is all because of this charming muted light that makes you feel prone to continue this acquaintance.
Scientists from Michigan conducted a study which included rats, and found out interesting data. Bright light such as daylight or just well-lit room makes you feel more, well, reasonable, able to assess the situation judiciously.
On the other hand, dim light lulls your vigilance. Muted light leads to 30%-decreased fuction of the hippocampus which is responsible for learning and memory abilities. Also there are decreased levels of specific brain substance which enables your neurons to communicate with each other. All this results in your poor ability to navigate and often make reasonable decisions.
Fortunately, in this study it was also shown that changing the dimly lit place into brightly lit one repays you your wisdom.
So, try to date with pleasing partners and there will be no disappointment afterwards. And, in case you feel "it is not quite your type" and you are too relaxed than you shoud be, you'd better choke this candle and turn on the light:)