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Email: [email protected]
3
The Extended Continuity Thesis, Chronocentrism, and Directed Panspermia
Milan M. Ćirković
Astronomical Observatory of Belgrade, Belgrade, Serbia
Abstract
The continuity thesis as formulated by Iris Fry has a strong appeal not only in the origin of life studies, but as a unifying principle bridging the gap between physical and life sciences. It is one of the most powerful methodological tools of contemporary astrobiology, especially in its efforts to build a synthetic view of the place of life and intelligence in the widest, cosmological context. Here, I briefly survey several of its key aspects and identify several open problems that it might be able to help with. Two particularly interesting aspects of the continuity thesis not discussed so far are its relation to the chronocentric bias and the application to panspermia hypotheses, especially the theory and practice of directed panspermia.
Keywords: Astrobiology, evolution, history and philosophy of science, abiogenesis, panspermia, extraterrestrial intelligence, physical eschatology
Who has cleft a channel for the torrents of rain, and a way for the thunderbolts, to bring rain on a land where no man is, on the desert in which there is no man; to satisfy the waste and desolate land, and to make the ground put forth grass?
The Book of Job 38: 25-27
He [Eddington] told me once, with evident pleasure, that the expanding universe would shortly become too large for a dictator, since messages sent out with the velocity of light would never reach its more distant portions.
Sir Bertrand Russell1
3.1 Introduction: The Continuity as a Pre-Requisite for Scientific Grounding of Astrobiology
In the course of last quarter of century, there has been a dramatic surge of interest not only in the novel synthetic field of astrobiology but also in the epistemological and methodological grounding of life sciences in a wider, cosmological context. Clearly, such philosophy of astrobiology should connect both with traditional disciplines of philosophy of physics (notably cosmology) and philosophy of biology and with what is happening in the foundations of life sciences and origin of life studies. This is a tall order by any standard and it is unlikely that we can make anything but an outline of the first small steps in the desired direction at the moment. However, it is also a challenge, since such a synthesis could help both in grounding of the existing research programs in astrobiology and in provoking the emergence of entirely new, so far unconceived ones. In the present chapter, we shall consider just a speculative example of the grounds to which a minuscule segment of the emerging synthesis could lead us. While it will undoubtedly be criticized as overly speculative, it could be argued that the exercise is still justified in terms of thought-provocation and structuring of our imagination. In the spirit of Eddington’s thinking cited above: although it probably is far-fetched to imagine that dictators will be around by the time intergalactic travel is developed, it is both morally and cognitively satisfying to think, even now, of ways to thwart them.
A great advance in the nascent philosophy of astrobiology has been introduced by the work of the Israeli philosopher of biology Iris Fry, who in several papers and an excellent book, The Emergence of Life on Earth, elaborated a key principle for the scientific study of the origin of life, or abiogenesis. This principle she calls the continuity thesis ([3.28], p. 389):
This common element, which I will coin “the continuity