Which term best describes the philosophy that expects life to be defined only by physical components?

The term that best describes the philosophy expecting life to be defined solely by physical components is Mechanism. This perspective views organisms and life processes primarily as mechanical systems, breaking down biological functions into physical interactions and chemical reactions. Under mechanistic philosophy, everything about living beings can be explained through physical laws and processes, without accounting for any non-material aspects like spirit or mind.

This philosophy contrasts with Vitalism, which posits that life is driven by a vital force that cannot be fully explained by physical or chemical interactions alone. Substance dualism also suggests that there is a distinction between the mind (or soul) and the body, while critical theory typically pertains to social, cultural, and political critiques rather than a framework for understanding life and existence. Mechanism's focus on the physical aspects offers a comprehensive understanding of living organisms in terms of their tangible parts and processes.