Since the 1960s there has been an alternative move within theory of science towards an understanding, according to MacKenzie & Spinardi (1995) that techno-scientific knowledge is no longer to be viewed as objective – in the sense of being “subject independent”; neither is it context independent, and it is not determined by the rule of scientific method. Instead scientific knowledge is situated, it happens locally, it is person-specific, and scientists do not follow rules but specific courses of action determined by the specific research environment and epistemic culture in which they are included (MacKenzie & Spinardi 1995:44). In this paper, I will discuss this view with specific emphasis on mind its tacit nature with regard to knowledge, i.e. what the tacit of “tacit knowledge” is and how it is embodied in technoscientific practice – I will thus attempt to shed light on the mind and in particular the act of thinking that takes place before and during the formation of knowledge. However, the messy task of dealing with mediations may be a means to access that peculiar pre-conscious act we call thinking, which grounds rationality, and is a ground common to us all.