When trying to understand our own or other people’s behaviour, we tend to oversimplify things. We use one or two adjectives to sum each other up. For example, we may think of some friends as having a generally hopeful and positive outlook while others are considered pessimistic and negative. Of course, in reality none of us is so easily defined. The truth is that we are all made up of characteristics which are inconsistent and contradictory: we can be serious and reliable with our colleagues at work but we are more unpredictable and emotional with our nearest and dearest at home. With one person we can be very cautious, but with another one, we are adventurous thrill-seekers. So, can people be neatly divided into personality types? Or do we alter our personality according to the differences in our changing moods and situations? Perhaps the idea that personality is fixed is just a meaningless misconception. Maybe we can never truly understand ourselves or other people.