In near future, billions of computers and intelligent sensors will connected through networks, each computer/application have its own autonomy, heterogeneity, and always in changing environments. We call these systems as a Heterogeneous Autonomous Decentralized Systems (HADS). Assurance is a hot research topic in HADS. In this paper, the conventional viewpoint towards assurance and the biological viewpoint for assurance are reviewed. Based on the biologically inspired matters, we view the assurance problem of HADS from system perspective, data perspective, communication perspective, and application perspective. An assurance definition in HADS is defined and its technical vision is figured out. It will help researchers for their research on assurance in HADS.