Haven't we all been in this state? The questions that are of interest here are: 1. How is this state possible in our mind? and 2. How sure can we be of this intuition that we know? i.e. Do we really know, what we think we do? But as is the case with all philosophical quests, we have to begin with what is it to know? So in the first part let us try and answer this question. Now, Does to know mean to have a prior knowledge of? Then again it becomes recursive..so obviously we are mixing words here.When we say prior knowledge of we mean prior information to the characteristics of the object and also of how we reacted to the subject, that what we felt when we encountered it/him/her/them etc. in past. So knowledge is a set of information which we created, based on the past experience, of that object , and stored it in our memory. Here the note reads: when i say "we created" ,i mean created by our processor (brain) based on the analogies derived from its database (the past exp