Anonymous Murder Called Infection – Invisible Life and the Question of Responsibility –

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Humans tend not to recognize what does not move as living. This cognitive bias fundamentally shapes how life itself is perceived and ethically evaluated. Microorganisms and viruses do not walk, gesture, or express intention. As a result, they are often treated not as living entities but as abstract phenomena—conditions, risks, or background variables. Yet these invisible and seemingly static forms of life exert decisive influence over human survival and death.

Microorganisms and viruses are intrinsically ambivalent. Humans derive immense benefits from microbial life: gut microbiota sustain metabolism, immunity, and physiological balance. At the same time, these same biological systems can become lethal threats through infectious disease. Despite this duality, such forms of life are rarely framed as “living beings.” Instead, they are reduced to tools, hazards, or statistical factors, stripped of moral and existential weight.

Deaths caused by infectious disease often originate in ordinary, banal circumstances. A cough in a crowded train, an unnoticed transmission, an asymptomatic encounter—these are sufficient to initiate a chain of events that may end in death. Such deaths occur with a frequency comparable to traffic accidents or acts of violence, yet they are rarely perceived as such. No perpetrator is identified, no intent is assumed, and responsibility dissipates into anonymity.

Infection produces death without malice. Because invisible life intervenes, the ethical narrative dissolves. The absence of clear intention allows death to be naturalized, depersonalized, and normalized. However, the outcome is no less final. Someone has died as a consequence of human proximity, behavior, and biological exchange.

In this sense, human beings exist simultaneously as potential perpetrators and potential victims. One may transmit infection without awareness or intent, and one may perish through the ordinary actions of others. The boundary between killing and being killed is unstable, porous, and continuously crossed. To live socially is already to participate in this mutual vulnerability.

This reality is deeply uncomfortable and therefore often ignored. Yet bioethics cannot confine itself to questions that are emotionally tolerable. The inability—or refusal—to recognize non-moving, invisible life as life constitutes a profound ethical blind spot. This blind spot shapes public health policy, risk perception, and the limits of social responsibility.

To acknowledge that one is, unavoidably, a being who may kill and may be killed is not an indictment of human cruelty. Rather, it is an honest recognition of coexistence with invisible life. Ethical engagement with biology must begin from this premise. Only by confronting the anonymity of infection and the diffusion of responsibility can life sciences and bioethics meaningfully address what it means to live—and die—together in a microbial world.