Nature

There is no definitive twentieth-century idea of nature. The turn of the century marked the beginning of a virtual revolution in the work that collectively constitutes the new physics. Albert Einstein's (1879–1955) theory of special relativity challenged the Newtonian notion of absolute space and time. And yet Einstein's theories did not support conceptual relativism. He was a Parmenidean in modern guise. God, in his account, did not play dice with the universe. Einstein dedicated the last half of his life to discovery of what came to be known as God's equation—a mathematical expression of the fundamental reality that explains all that there is, was, or will be.

The middle of the twentieth century might be represented through the work of Werner Heisenberg (1901–1976). If Einstein is a Parmenidean, then Heisenberg's principle of indeterminacy and quantum theory manifest a Heraclitean vision. In his account, the very activity of the observation of nature made a profound difference in what was observed. Physical sciences could achieve relative precision in one measurement only by sacrificing certainty in another. Heisenberg's insights into the atom were equally brilliant. The particles within atoms did not, Heisenberg demonstrated, behave according to Newtonian mechanics. While the picture of nature offered by classical physics remains useful in certain domains—for example, calculating the trajectories of flying objects or predicting the motions of planets and stars—the Newtonian view has lost intellectual hegemony.

The latter decades of the twentieth century can be represented by work of another Nobel laureate, Ilya Prigogine (1917–2003). Prigogine and many others constitute a rapidly growing epistemic community studying the phenomena of nature that are in disequilibrium—including life itself. After embracing chaos theory, the possibility of definitive description disappears, as does the notion that complex phenomena can be disassembled into constituent parts and then reassembled. Biological and ecological scientists in particular have challenged reductionistic mechanism. The principle of superposition, which underlies the description and explanation of linear phenomena, has been repudiated by the life sciences, where nonlinearity rules.

The implications of such accounts for our idea of nature, as well as the conceptualization of our place in nature, are enormous. The belief that humankind has sure and certain knowledge of nature is untenable. While remaining useful assumptions at some scales of inquiry, atomism, reductionism, and mechanism are not absolutes. Laplacian determinism, the notion that, given sufficient knowledge of nature, sure and certain prediction of the future is possible, has been discredited. Radically new perspectives on the nature of nature and the cosmos itself have started to emerge. Time itself has clearly been recognized as a fourth and absolutely essential dimension of any comprehensive idea of nature.

The notion that humankind has dominion over the evolved world has also been discredited. Our knowledge of nature is limited, more contingency and probability than necessity and certainty. Increasingly the lack of equilibrium in the natural world gives evidence that our present interactions with it are unsustainable over biologically and ecologically meaningful scales of time. Political and economic temporal scales are known to be discordant with nature's temporal horizons. The fragility of humankind's dominion is clearly manifest in multiple dysfunctional relations between cultural and natural systems. Despite the received idea of nature, nature profoundly acts on culture. The idea of nature as a passive material world over which humankind has dominion has failed, gravely intensifying the question of humankind's place in nature. Conceptual developments in areas such as cosmology also lead to a chastened view of our place in nature. The visible material cosmos is a very small portion of reality. Dark matter, as it turns out, while unseen, is as consequential in understanding the cosmos as visible matter.

As the twentieth century ended, the notion of a discord between the culturally dominant idea of nature and nature itself gained credence. The cultural system, which had given birth to and nurtured the idea of nature as passive matter in motion, subject to reductionistic explanation and technological control, began to experience pervasive environmental dys-functions. The anthropogenic depletion of stratospheric ozone, collapse of oceanic fisheries, deforestation of Amazonia, disruption of global weather patterns, and extinction of biodiversity posed ominous warnings as well as major conceptual challenges that can only be met by articulating alternative ideas of nature and humankind's place therein.