Knowledge acquirement

I often find myself comparing my own behavior in a situation with somebody whom I knew in a similar situation. It feels like I can draw parallels and understand my own and their behavior better. Was wondering to which degree does it make sense to draw parallels and if I can use it in my research. For example - can I predict the development of the situation taking into consideration that I'm aware of the comparison and will look at it before making choices? Can I use an individual's experiences to suggest conclusions? Probably should be careful there - need to read more about qualitative research approach