Vitalism is a belief that starts from the premise that "living organisms are fundamentally different from non-living entities because they contain some non-physical element or are governed by different principles than are inanimate things." Where vitalism explicitly invokes a vital principle, that element is often referred to as the "vital spark", "energy", "élan vital", "vital force", or "vis vitalis", which some equate with the soul. In the 18th and 19th centuries, vitalism was discussed among biologists, between those who felt that the known mechanics of physics would eventually explain the difference between life and non-life and vitalists who argued that the processes of life could not be reduced to a mechanistic process. Vitalist biologists such as Johannes Reinke proposed testable hypotheses meant to show inadequacies with mechanistic explanations, but their experiments failed to provide support for vitalism. Biologists now consider vitalism in this sense to have been refuted by empirical evidence, and hence regard it either as a superseded scientific theory, or, since the mid-20th century, as a pseudoscience.

Henri-Louis Bergson was a French philosopher, who was influential in the traditions of analytic philosophy and continental philosophy, especially during the first half of the 20th century until the Second World War, but also after 1966 when Gilles Deleuze published Le Bergsonisme. Bergson is known for his arguments that processes of immediate experience and intuition are more significant than abstract rationalism and science for understanding reality.