I think we can remove "white lies" from the equation, as we all understand that these are simply a mechanism with which we oil the wheels of social interaction, often to avoid causing hurt. As for those who often lie about virtually anything, we tend to refer to them as pathological liars. Such people lie for a variety of reasons. Self-protection, self-aggrandizement, financial or social gain, or sometimes even in attempt to obscure bad behaviour. Even though we quite often recognise that this is happening, we perhaps still pity the self-deluding behaviour. At the top end of the scale are those who routinely and knowingly lie, usually for personal gain, and often at the expense of others. We are rightly much less forgiving about them. Such people often lie their way into positions of power, (no names, no pack-drill), and continue to do so in order to promote their survival. This group can be described as sociopathic, or as having an antisocial personality disorder. This type of behaviour can even bring them into conflict with the law. So why do people lie? For many reasons, and at many levels. I suspect that we all know or at least have knowledge of people in every category.