Falling in love is natural and spontaneous for everyone and we all fall in love once or more in one life span. You might hear many stories about love at first sight. Love is nothing just an affectionate behavior for someone as per psychology, scientifically it is a hormonal effect over our neurological brain and spiritually loves is sacrifice for loved one.
Psychologically love occurs due to our thought process and some criteria fixed by our brain. If you are single then you definitely fix some criteria in your mind for a dream girl. How did she look? Skinny or fatty: what should her education be? Graduate or undergraduate: what should her personality be like? Silent or talkative and the list is endless. Suppose you find someone who matches your criteria, which will create the love at first sight.
Scientifically love occurs due to some hormonal effects of our body. Some men get attracted towards women due to the smell of their menstrual cycle. Likewise, women like the smell of the testosterone and subconsciously fall in love. Some other hormones secrete from our body like adrenaline, dopamine and serotonin also play some major role in falling in love with someone.
Spiritually it is very easy. It is connected with the universal truth of unities. All soul is one and originated from the Supreme soul. So the attraction between souls to the soul is natural.