In this volume, the wording 'professional' and 'non-professional' is central to our discussion of concepts, since these notions reflect well the weighty aspect of the tension appearing at the junction of the private sphere of our life and the scientific one. Personal experience of each of us (the 'non-professional' part of our biography) continuously--consciously or unconsciously--gets imprinted in everything that is located in the area of 'professional' actions; from the choice of research areas to the ways of their theoretical and methodological conceptualization.