Abstract
Complex technology has become an essential aspect of everyday life. We rely on technology as part of basic infrastructure and repeatedly for tasks throughout the day. Yet, in many cases the relation surpasses mere reliance and evolves to trust in technology. A new, disruptive technology is blockchain. It claims to introduce trustless relationships among its users, aiming to eliminate the need for trust altogether—even being described as “the trust machine”. This paper presents a proposal to adjust the concept of trust in blockchain applications with the tools provided by conceptual engineering. Its goal is to propose a concept of trust, that offers more than a halo term, devoid of the normative depth that the original, philosophical term actually carries. To evaluate possible concepts of trust in blockchain applications, five criteria are proposed: These criteria ensure that the conceptual relation indeed embodies trust, thereby being richer than mere reliance, and that the chosen concept highlights the active role of the trustor. While the concepts of trust in engineers and trust in algorithms have to be discarded, institutional trust emerges as a viable candidate, given some refinements. Ultimately, the concept of trust by normative expectations and attribution is suggested to capture the essence of trust in blockchain applications.