Cambridge University Press 978-0-521-19775-5 - the Astrobiological Landscape: Philosophical Foundations of the Study of Cosmic Life Milan M

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Cambridge University Press 978-0-521-19775-5 - The Astrobiological Landscape: Philosophical Foundations of the Study of Cosmic Life Milan M. Ćirković Index More information

Index

Page numbers in italic denote ﬁgures.

A-Life (artificial life) 96 navigation errors 104 age of universe 53 role of astrobiology 95–98 Aguirre, Anthony, ‘cold’ Big Bang model 98–99 ‘Archipelago of Observership’ 146 altitude weighting 101–102 Areoparadise Lost 11, 82, 207 amino acids, L-enantiomeres 12–13, 207 Aristotle (384–322 BC), cosmology 37 Anaxagoras of Clazomenae (5th century BC), Arnold, Luc, detection of artificial transits 195–196, worldview 42, 46 200 Anaximandros (6th century BC), cosmology 42 artificial transit detection, work of Luc Arnold Annis, James, global regulation mechanism 159–161 195–196, 200 anthropic argument see Carter, Brandon, anthropic artificial vs. natural 188–196, 212 argument asteroid impacts 187 anthropic fine-tuning 66–72 mass extinctions 117–118, 187 anthropic principle 30–31, 88 role of Jupiter 135–137 alternative life forms 95–96 astrobiological landscape 23, 80, 78–85, 181 Davies–Tipler argument 38–39, 40 constraints 81–84 misconstruction 100 astrobiology misuse 102 anthropic reasoning 70 participatory 68 and Copernicanism 21 Signor–Lipps effect 64 and cosmology 23, 28–55, 208, 211–212 strong 142 early days 49–51 anthropic reasoning 69–72 historical parallel 49–55, 173 astrobiology 70 philosophy 51–52 as last resort 105–106 research discourse 52–53 Olum’s problem 72–78 critical theses 15–19 Simplicio–Salviati ‘dialogue’ on 102–107 and Darwinism 129 anthropocentrism 39, 100 ‘deep questions’ 208 overcoming 25 definition 9–10 religious, criticism of SETI 162–163 discoveries, importance to evolutionary theory 127 see also exceptionalism, human dynamics 167 anthropomorphism 184 extended mandate 21, 23, 206, 203–215 antimatter burning, gamma-ray search 177, 178–179, and future studies 210 200 and laws of physics 204–205, 208 apeiron 42 and mapping Archipelago of Habitability 95–98 apparent design 188–189 misunderstandings 21–22 Archipelago of Habitability 23, 91, 89–93, 208, neo-Copernican synthesis 205–208 211–212 numerical simulation 121–122 basic conditions 96 pace of discovery 15, 16 changing parameters of physics 98 and philosophy 19–20, 52, 150

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260 Index

astrobiology (cont.) Carter, Brandon popularization 53 anthropic argument 150, 156–161 revolution 8, 207 criticism by Wilson 158–159 self-reﬂection 208 catastrophes strangeness 208 destruction of life forms 74, 159–161 testability of hypotheses 17 extinction probability 83, 84 unifying concept 209 ceteris paribus, unphysical 134–135, 180 work of Sir Fred Hoyle 54 Rare Earth hypothesis 135–138 astroengineering, strangeness 198–202 Chaisson, Eric, on cosmic evolution 144, 209 astronomy, extragalactic 60–61 chirality 12–13, 114–115, 207 asymmetry, biological 12–13, 207 circumstellar habitable zone, Rare Earth hypothesis asymptotic giants 60 131 atoms, formation of 35 civilizations, work of Ken Olum 72–74, 75–77, 104 cognitive distance 128 Bacon, Francis (1561–1626), view of legitimate coherence gap 134, 135 science 106 cold Big Bang model 98–99 Barnard’s Star 60 communication, extraterrestrial, radio waves 187–188 Basalla, George, Civilized Life in the Universe (2006) complexity, Archipelago of Habitability 96 163–164, 170–172, 174–175 consilience 22, 55, 206–207 Bayesian formulations 61 contamination, extraterrestrial 8 Benner, Steven, on astrobiology and philosophy 19 contingency 116–117 Bertka, Constance, on origin of life 11 biological 150, 151–156 BigBangtheory vs. convergence argument 119–125 cold 98–99 continuity thesis 132, 141–143, 168–169 relativistic hot 34–36 extended 143–144 vs. steady state theory 33–34 and Rare Earth hypothesis 146–147 biodiversity, Mars 110–111 resistance to 182 biogenesis 11–12, 82–83, 120, 207 convergence 119–125 continuity thesis 132, 141–143 vision 123–124 low probability of random assembly 142, 143 work of Geerat J. Vermeij 122–123 ‘lucky accident’ argument 120, 142, 143 Conway Morris, Simon, convergence 119–120, 123 Rare Earth hypothesis 132 Copernican Principle 7 biology Copernican revolution 20–21, 56, 211 universal concepts 111 Copernicanism 56, 161, 205–206, 210 universal laws 110 and astrobiology 21 impact on astrobiology and SETI 128 and Rare Earth hypothesis 133, 144 biosphere, shadow 127 see also neo-Copernicanism ‘Black Clouds with a Vengeance’ scenario 81 Cosmic Habitable Age 158 Boltzmann brains problem 104–105 cosmic microwave background 34 Boltzmann–Zermelo debate 33 cosmogony, ‘perennial problems’ 40–41 Bolzmann, Ludwig see Boltzmann–Zermelo debate cosmological constant 90, 93–94 bombardment see asteroid impacts cosmology Bondi, Hermann (1919–2005), steady state theory and astrobiology 23, 28–55, 208, 211–212 47–49 early days 49–51 Bostrom, Nick, Anthropic Bias 103 historical parallel 49–55, 173 boundary conditions 113–114 philosophy 51–52 Brin, G. D., Great Silence paradox 178–179 research discourse 52–53 Brownlee, Donald, Rare Earth hypothesis 130, work of Wallace 28–29 131–133 biophysical 27 bubble universes 49, 88 cyclic, Empedocles of Acragas (5th century BC) Burgess Shale, ‘rewinding the tape of life’ 115–116 39–40, 41 see also Gould, Stephen Jay factual 50 ‘Great Controversy’ 33–34, 49, 133 cabin of contact, intelligent species detectable by observation selection humans 154, 155–156 anthropic ﬁne-tuning 66–72 Cambrian Explosion 115 Signor–Lipps effect 64 see also ‘rare’ Cambrian explosion analogues philosophy of 51–52, 182 Canonical Three 11–12 physical, modern 32–36

Index 261

popularization 53 Empedocles of Acragas (5th century BC), cyclic work of Wallace 29–32 cosmology 39–40, 41, 46 counterfactuals 66 encephalization quotient 154 historical causation 134–135 end-Permian mass extinction 154 creationism 138, 142 Enlightenment quest 207, 208–209, 211, 212 Cuzanus, Nicolas, De docta ignorantia (1440) 37 equilibrium, punctuated 161 Ernst, Max (1891–1976), Anthropomorphic Figure ‘Daisyworld’ thought experiment 122 with Shell Flower (1931) 184, 185 dark energy 34 eschatology, physical 210, 213 dark matter 93 eternity, distinction from time 37 Darwin, Charles (1809–1882), entangled bank Euclid, definitions 9 metaphor 78–79, 109 eukaryotes, Earth without 125, 126 Darwinism 20, 23 Europa, ocean 125, 126 and astrobiology 129 everlasting, distinction from eternity 37 and Newtonian mechanics 109–110 evolution universalism 112–113 Charles Darwin, entangled bank metaphor 78–79 Davies–Tipler argument 38–39, 40 convergence 119–125 de Sitter spacetime 104–105 cosmic 34–36 de Sitter, Willem, empty universe model 33 work of Eric Chaisson 144, 209 ‘Dead Space’ scenario 80, 81, 84 Darwinian 10, 112–113 decoupling, of matter and radiation 35 and extended continuity thesis 144 definitions 9–10 numerical simulation 121–122 design see apparent design; Intelligent Design; postbiological 174, 200 intentional design evolutionary theory, importance of astrobiological design hypothesis 68–69 discoveries 127 detectability, of extraterrestrial intelligence 178–179, exaptation 22 189, 200, 202 exceptionalism, human 211 Dick, Steven J. expanding universe 33 postbiological evolution and SETI 174, 200 ‘Extinct Galactic Club’ scenario 81 The Biological Universe (1996) 27–28, 174 extinction probability 83, 84 Dirac, Paul (1902–1984), large number near-equality extinctions see gamma-ray bursts; mass extinctions 66–67 extragalactic distances, determination 60–61 diversity, see also biodiversity extrasolar planets, evolutionary simulation 121–122 Drake equation 164, 165, 169–170, 176 extraterrestrial civilizations 101 dynamical parameters 79 detection 199 Dyson, Freeman on astroengineering 198–199, 200–202 ‘False Precision’ scenario 80, 81 detection of extraterrestrial civilizations 199 Fermi’s paradox 46, 83, 83–84, 149, 178–179, 211 extraterrestrial infrared radiation 177, 199 criticism by Pigliucci 178 Dyson shell 127, 128, 177, 178–179, 199, 200, 201 Henry Stop thought experiment 178, 179–181 work of Stanislaw Lem 214 Earth see also Great Silence paradox influence of Jupiter 135–137 Fiasco argument 154–156 influence of Moon on obliquity and rotation 137 final causes, ideas of Hutton 43–44 loss of water 125–126 fine-tuning, anthropic 66–72 ‘Earthsea’ 94 brute fact explanation 67–68 Eddington, Sir Arthur (1882–1944) co-emergent with observers 68 cosmology 33 intentional design 68–69 Malmquist bias 59 multiverse hypothesis 69 popularization of cosmology 50 finiteness, human history 41–42 Eddington–Lemaˆıtre universe 45–47 Flatland 73 effective past, finite 46 flux-limited samples 60 Einstein, Albert (1880–1952), static universe model football, observation selection, fine tuning 65 33, 45 fossil record, extinctions 61–64, 65 electrons 35 freak observers 104–105 elements Friedmann, Alexander (1888–1925) 33 formation 35–36 Friedmann universe 88, 93, 105 four classic, of Empedocles 39 Fry, Iris, continuity thesis 132, 141–143, 168–169

262 Index

future studies homogeneity, of universe in four-dimensional and astrobiology 210 spacetime 47–48 astroengineering 198–199 hostility parameter 75 Hot Big Bang 34–36 ‘Galactic Club’ scenario 81, 83 Hoyle, Sir Fred (1915–2001) 53–54 Galactic Habitable Zone (GHZ) 21, 22, 83–84 astrobiological science fiction 54 and gamma-ray bursts 159–160 fine-tuning, nuclear resonance of carbon 71–72 non-uniform distribution 30 popularization of cosmology 50 Rare Earth hypothesis 131, 139 steady state theory 47–49 galaxies Hubble constant 48–49, 53 age distribution, steady state model 48–49 Hubble, Edwin Powell (1889–1953), expanding density 92 universe 33 preconditions for life 92–93 Hutton, James (1726–1797), ‘world machine’ gamma-ray bursts 74, 75, 84 43–44 global Galactic regulation 159–160 gamma-ray SETI search 177, 178–179 imagination, and the astrobiological revolution 22 Gamow, George (1904–1968) impact frustration expanding universe 33 early life forms 159 factual cosmology 50 macro-evolutionary punctuation 117–118 popularization of cosmology 50 induction Gardner, James N., Selfish Biocosm hypothesis 213 and SETI 164–170 global regulation mechanism 159–161 marble thought experiment 165–167 global risk management 211 telephone cable thought experiment 166–167 Gold, Thomas, steady state theory 47–49 inertial interchange events, and development of Goodfield, June, on origin of universe 173 complex life 132 Gould, Stephen Jay (1941–2002) infinity, Eddington–Lemaˆıtre universe 46–47 Earth without eukaryotes 125, 126 inflation ‘rewinding the tape of life’ 115–116 chaotic 49, 88 on Wallace’s anthropic principle 30–31 and the multiverse 88 gradualism 7, 64, 159 inflationary paradigm 73 Great Controversy, cosmology 33–34, 49, 133 information paradigm 88 Great Silence paradox 178–179 information processing 200 Greece, Ancient, cosmological ideas 39–43 infrared radiation, SETI 177 Gregory, Andrew, on Greek cosmological initial conditions 120 ideas 40–41 sensitivity to 116–117 intelligence habitability 82–83 definition 10 continuous 157–158 evolution of 153, 152–153 Rare Earth hypothesis 132 extraterrestrial see also Archipelago of Habitability astroengineering 198–202 habitable zone see circumstellar habitable zone; biological contingency 151–156 Galactic Habitable Zone (GHZ); habitability; detectability 178–179, 189, 200, 202 stars, habitable information processing 200 Haldane, J. B. S. (1892–1964) recognition protocol 197–198 complex life, lack of imagination about 140 strangeness 184–185 cosmology 45 unconscious general and intelligent life forms 31 David M. Raup 186–188 Haldane’s ladder 145 noise 187–188 Haldane’s law 140 see also noogenesis; observers, intelligent single continuum 145 Intelligent Design 138 halo artefacts 200 misuse of anthropic principle 102 Harris, M. J., gamma-ray SETI search 177, 200 intelligent observers 145–146, 151–156 helium, Lockyer’s conspiracy 133–134 minimal conditions for 96 Herschel, Sir William (1738–1822), stellar intentional design 188–189 system 29 ionization temperature 35 hierarchy, biological 127 iridium anomaly, asteroid impact 187 history of ideas, misuse 172–173 island, Archipelago of Habitability 90, 98–100 homochirality 13, 67 ‘altitude weighting’ 101–102

Index 263

Jupiter Mach, Ernst (1838–1916), opposition to atomic theory period of revolution 58 87 as shield against bombardment 100, 135–137 macro-engineering, extraterrestrial 177, 198–202 see also ‘rare’ Jupiter macro-evolution, punctuated 117–118 Magritte, Rene´ (1898–1967) K/T boundary extinctions 62, 187 The Beyond (L’au-dela)` (1938) 189, 189–191, 212 Kant–Laplace theory, formation of Solar System 7 The Domain of Arnheim (1938) 191, 191–193 Kapteyn, Jacobus Cornelius (1851–1922), model of main sequence giants 60 universe 29 Malmquist bias Kardashev Type 3 civilization 49, 164, 200 extragalactic astronomy 60–61 Kircher, Athanasius (c.1601–1680), calcite observation selection 59–61 ‘inscriptions’ 194–195 Malmquist, Gunnar (1893–1982) 59 kosmos 41, 85 Mars biodiversity 110–111 L-enantiomeres 12–13, 207 ‘canals’ 8 Lake Vostok, metazoans 125 Kant–Laplace theory 7 Leibnitz–Berkeley–Machian relationist theories 46 microfossils and biogenesis 11–12, 82, 207 Lem, Stanislaw (1921–2006) as seen by Spirit rover 190, 190 evolutionary universalism 112–113 Martians, as intelligent species, H. G. Wells 7 Fiasco (1987) 154, 197–198 Mash, Roy, big numbers and induction in SETI Silentium Universi 178 164–170 The New Cosmology (1971) 214–215 mass extinctions Lemaˆıtre, Georges (1894–1966), expanding universe asteroid impact 117–118, 187 33 duration 61–64 see also Eddington–Lemaitre universe end-Permian 154 life K/T boundary 62, 187 alternative forms 17–18, 23–25, 95–96 Signor–Lipps effect 63, 64 artificial 96 see also gamma-ray bursts Canonical Three 11–12 Matrioshka brains 177, 178–179 catastrophic events 74 Mazlish, Bruce, on continuity and astrobiology complex 203–204 effect of plate tectonics 158 megaverse 89 lack of imagination about 140 metallicity, extrasolar planets 58–59 Potsdam group model 139 metazoans 146 see also noogenesis extraterrestrial, radio communication 187–188 definition 9–10 ‘TwinEarth’ 121 hospitality of universe 74 meteorites origin of 11–12 chiral asymmetry 13 possible diversity 18 organic compounds 17 preconditions for 74, 204–205 microfossils, and biogenesis 11–12, 82 Rare Earth hypothesis 132 microorganisms, contamination of space 8 Linde, Andrei, chaotic inflation 49, 88 Milky Way galaxy Lineweaver, Charles, cosmology and astrobiology age 48–49 54–55 astrobiological scenarios 80–81 living systems constraints 81–84 asymmetry 12–13, 207 constraints on panspermia 81–82 link with laws of physics 204–205 Rare Earth hypothesis 131–133 ‘Lockyer’s conspiracy’ 133–134 Milne, Edward Arthur (1896–1950), two timescales Love, attractive interaction 39, 40, 46 cosmological model 45 Lovecraft, Howard Phillips (1890–1937), The Colour Mind, and finite origin of motion 42 Out of Space (1927) 23–25, 188 Moon Lowell, Percival, Martian ‘canals’ 8 influence on Earth 137 Lucretius, Titus Lucretius Carus (1st century BC), on see also ‘rare’ Moon finite world 43 Moore’s law 15 Lutyen’s Star 60 morphology, regular 193–194, 194 Lyell, Sir Charles (1797–1875), gradualism 7 morphospace, evolution of intelligence 151–152, 153, 154–155, 169 M-theory 73, 88–89 motion, finite origin of 42, 46

264 Index

multicellularity 132 panspermia hypothesis 8, 54, 120 multiverse 49 Milky Way galaxy 81–82 multiverse hypothesis 69, 87–89, 204–205 parallelism 123, 124 Archipelago of Habitability 89–93 Parmenidian timeless philosophy 74 and inflation 88 participatory anthropic principle, John A. Wheeler 68 mutational ordering 117 Particle physics, and astrobiology 211–212 Pearl-Katar 196, 196 NASA perfect cosmological principle (PCP) 47–48 ‘Astrobiology Roadmap’ (1998) 10 Permian see end-Permian mass extinction definition of life 10 philosophy The Astrobiology Institute 210 and astrobiology 19–20, 52, 150 natural selection cosmology, modern 51–52, 182 and man, work of Wallace 28, 32 physics, engineered by supercivilizations 214–215 and Newtonian mechanics 109–110 Pigliucci, M. universalism 112–113 on Fermi’s paradox 178 natural vs. artificial 188–196, 212 Henry Stop thought experiment 178, 179–181 naturalism 7, 18, 23 Nonsense on Stilts (2010) 175–176 neo-Copernicanism 205–206 Planck energy 49 synthesis 206–208, 213 planetary rings, artificial 177 New Standard Cosmology 34, 36, 88 planets Newtonian mechanics, and natural selection 109–110 extrasolar, observation selection 57–59 noise, unconscious intelligence 187–188 supramundane 200 noogenesis 7, 144–147 plate tectonics 186–187 biological timescales 158–159 and development of complex life 132, 158 effect of plate tectonics 158 extrasolar 138–139 resistance to 182 pluralism 28, 171 see also intelligence, evolution of Poe, Edgar Allan (1809–1849), The Domain of novelty 39–40 Arnheim (1847), natural and artificial 191 nuclear reactions, formation of elements 35–36 Popper, Sir Karl (1902–1994), life on Mars 110–111 nuclides see ‘rare’ nuclides popularization, of cosmology and astrobiology 53 number, definition 9 Principle of Mediocrity 164–170, 205 Principle of Plenitude 133 obliquity, influence of Moon 137 Proclus of Athens (c. AD 410–485), solar eclipse observation selection 103–104 AD 484 110 cosmology, Signor–Lipps effect 64 protoplanetary disk, metallicity 59 extrasolar planets 57–59 Proxima Centauri, luminosity 60 metallicity of star 58–59 pseudoscience, SETI 150–151, 162, 175–176 temporal scale 58 punctuation, macro-evolutionary 117–118 fine-tuning 65–72 football 65 quasi-stellar objects (QSOs) 61 Malmquist bias 59–61 mass extinctions, Signor–Lipps effect 64 radio communication, extraterrestrial 187–188 Olum’s problem 72–78, 104 random location 56 palaeontology 61–64 ‘rare’ Cambrian explosion analogues 131, 132, 143 observers see intelligent observers Rare Earth equation 132 Oikumene 42 Rare Earth hypothesis 57, 80, 81, 130–147 Olbers’ paradox 33 and Copernicanism 144 Olum’s problem 72–78, 104 criticism 133–141 O’Neill habitats 177, 200 and extended continuity thesis 146–147 orbital rings 200 and Galactic Habitable Zone (GHZ) 131, Orellana, Francisco de (1511–1546), discovery of 139 Amazon 86 key requirements 131–133 Ouroboros symbol 13–15 lack of imagination about complex life 140 overspecification 167–169, life forms 132 192 low probability of contingent events 140 Ozma Project 177 scepticism 140–141 unphysical ceteris paribus 135–138 palaeontology, observation selection 61–64 ‘rare’ Jupiter 131, 135–137 Panglossianism 70–71 ‘rare’ Moon 131, 137, 139

Index 265

‘rare’ nuclides 131 Steven J. Dick, postbiological evolution and SETI Raup, David M., unconscious intelligence 186–188 174 re-ionization of matter 35 strangeness 184–185 recognition protocol 197–198 towards coherent philosophy 181–183 ‘Red Dwarf Kingdom’ scenario 81 shadow biosphere 127 red dwarfs 60 Shanahan, Timothy, on Darwinism 20, 112 red giants 60 shell worlds 200, 201 reductionism 18 Signor–Lipps effect 64–65 ‘Regis III’ scenario 112–113, 116, 118, cosmology 64 120 Earth sciences 62, 63, 64 regularity, in morphology 194, 193–194 Silentium Universi 178 religion, criticism of SETI 162–163 Simplicio–Salviati ‘dialogue’, anthropic reasoning rhodopsin 123 102–107 RNA world 11 Simpson, George Gaylord (1902–1984), biological Rome, Ancient, cosmological ideas 43 contingency argument 18, 150, Ruse, Michael, on Popper and evolution 111 151–156 Sloan Digital Sky Survey (SDSS) 36 scepticism, Rare Earth hypothesis 140–141 Sloan Great Wall 86 Schiaparelli, Giovanni Virginio (1835–1910), Martian Smolin, Lee, on anthropic reasoning 71–72 ‘canals’ 8 Snowball Earth Schrodinger,¨ Erwin (1887–1961), What is Life? and development of complex life 132 (1944) 9–10 on Earth analogues 157–158 science fiction, work of Sir Fred Hoyle 54 solar eclipse AD 484, Proclus of Athens 110 selection see observation selection Solar System, typicality 53, 56, 57–58 self-propagation, universe 47–48 space elevators 200 Selfish Biocosm hypothesis, James N. Gardner 213 species stratigraphic range 62 SETI 101, 148–183, 210 spectroscopy, metals, extrasolar planets 58–59 and continuity thesis 147 ‘Sporadic Life’ scenario 80, 81 criticism 161–181 Stapledon, Olaf, Star Maker (1937) 213–214 the ‘Big Three’ anti-SETI arguments 149–161 stars biological contingency argument 18, 150, first generation 35–36 151–156 habitable, Milky Way galaxy 81–82 Carter’s argument 150 Malmquist bias 59–60 extrascientific 162–163 second generation 35 Fermi’s paradox 149 static universe model 33, 38, 45 Fiasco argument 154–156 stationarity 37–38, 49 philosophical 162, 163–174, 175–176, stationary universe 37–38, 39 182–183 steady state theory 39, 47–49 practices and methods 162, 174, vs. Big Bang theory 33–34 176–177 strangeness religious anthropocentrism 162–163 in astrobiology 208 evolution of intelligent observers 128 in astroengineering 198–202 extraterrestrial communication 187–188 complex life forms 140 extraterrestrial radio communication 187–188 extraterrestrial intelligence 184–185 gamma-ray search 177 recognition protocol 197–198 George Basalla, Civilized Life in the Universe Strife, repulsive interaction 39, 40, 46 (2006) 163–164, 170–172, string theory 88–89 174–175 multiverse 89 impact of universal biological laws 128 strong anthropic principle 142 infrared radiation 177 supercivilizations, work of Ken Olum 72–74, 75–77, M. Pigliucci, Nonsense on Stilts (2010) 175–176 104 natural vs. artificial 195–196 supergiants 60 need to take seriously 147 supernaturalism 28 as pseudoscience 150–151, 162, supernovae 35–36 175–176 Susskind, Leonard, string theory multiverse 89 as quasireligion 175 symmetry recognition protocol 197–198 left–right 12–13 Roy Mash, big numbers and induction spontaneous breaking 13 164–170 synthesis, neo-Copernican 206–208

266 Index

‘tape of life’, replay 115–116 static 33, 45 see also Gould, Stephen Jay stationary 37–38 ‘Tau Ceti Centre’ scenario 117–118, 126 bubble 49, 88 Tegmark, Max, Archipelago of Habitability 89 ‘weakless’ 99–100 Teilhard de Chardin, Pierre (1881–1955), noogenesis 144 vacuum states, low-energy 88, 89, teleology 28, 31, 103 91 temporal scale, observational selection 58 Vermeij, Geerat J., convergence 122–123 testing, of hypothesis 17 Vilenkin, Alexander, eternal inflation 49 Thalassiosira 194 vision, convergent evolution 123–124 thermodynamics 37–38 volume-limited sample 60 Thomson scattering 35 extragalactic distance determination ‘Threga IX’ scenario 119–120 60–61 Thucydides (c.460–c.400 BC), finiteness of history 41–42 Wallace, Alfred Russel (1823–1913) time, distinction from eternity 37 astrobiology 28–29 timescale cosmology 29–32 astrophysical Galactic Habitable Zone, non-uniformity and biological correlation 156–157, 158–159 30 continuous habitability 157–158 general and intelligent life forms 31 cosmological 53 Is Mars Habitable? (1907) 28, 31 Tolman, Richard (1881–1948), cosmology 33 Kapteyn model 29 Toulmin, Stephen (1922–2009), on origin of universe location of Earth and Solar System 17 173 Man’s Place in the Universe (1903) transcendence, intelligent communities 155 28–29 transhumanism 210 Ward, Peter ‘TwinEarth’ scenario 115, 116–117, 121 on astrobiology and philosophy 20 typicality 53, 56, 57–58 Rare Earth hypothesis 130, 131–133 water, and habitability 125–126 unconscious intelligence ‘weakless’ universes 99–100 David M. Raup 186–188 Weinberg, Steven noise 187–188 cosmological constant 90, 93–94 unification, work of Eric Chaisson 209 The First Three Minutes (1977) 50 work of E. O. Wilson 206–208 Wells, Herbert George (1866–1946), The War of the uniformitarianism 39, 159 Worlds (1897) 6–7 United Nations, Outer Space Treaty (1967) 8 Weyl postulate 46, 47 universalism, natural selection 112–113 Wheeler, John A. (1911–2008), participatory universe anthropic principle 68 age of 53 white dwarfs 100–101 eternal, Empedocles 39–40, 41 Wilson, Edward O., consilience 206–207 evolution 34–36 Wilson, P. A., criticism of Carter’s anthropic argument Hot Big Bang 34–36 158–159 New Standard Cosmology 36 Wren, Sir Christopher (1632–1723), St Paul’s finite age 38 Cathedral inscription 212 hospitality to life 74 infinite 73 Zermelo, Ernst see Boltzmann–Zermelo debate