Model-dependent realism

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In philosophy, model-dependent realism asserts that all we can know about "reality" consists of networks of world pictures that explain observations by connecting them by rules to concepts defined in models.

A world picture consists of the combination of a set of observations accompanied by a conceptual model and by rules connecting the model concepts to the observations. Different world pictures that describe particular data equally well all have equal claims to be valid. There is no requirement that a world picture be unique, or even that the data selected include all available observations. The universe of all observations possibly may be covered by a network of overlapping world pictures and, where overlap occurs; multiple, equally valid, world pictures exist, a form of ontological pluralism.

As a philosophical position, model-dependent realism is not a strict form of metaphysical realism (the world is as it is, independently of how humans take it to be), but contains features of the anti-realist position that the world is mind-dependent.[1] Like some anti-realist positions, model-dependent realism accepts conceptual relativism, the view that having multiple world-pictures that include the same observations is not a difficulty. However, the notion that the "world is as it is, independently of how humans take it to be" is not abandoned explicitly, but replaced by the notion that whatever the world may be, all we can know of it is conceptually relative, a network of overlapping world pictures.


Recently the connection between models and observations has been explored by physicists Stephen W. Hawking and Leonard Mlodinow in their book: The Grand Design, where they propose the notion of model-dependent realism, a view of reality based upon world pictures.[2] Hawking/Mlodinow introduce a world picture as follows:

... a physical theory or world picture is a model (generally of a mathematical nature) and a set of rules that connect the elements of the model to observations. This provides a framework with which to interpret modern science.[3]

This quotation defines a "world picture". The concept of model entering a "world picture" is extended to a wider class of mental concepts in the metaphysical position of model-dependent realism as proposed below:

According to the idea of model-dependent realism...our brains interpret the input from our sensory organs by making a model of the outside world. We form mental concepts of our home, trees, other people, the electricity that flows from wall sockets, atoms, molecules, and other universes. These mental concepts are the only reality we can know. There is no model-independent test of reality. It follows that a well-constructed model creates a reality of its own.[3]

Hawking/Mlodinow point out:

  • that either an earth-centered (Ptolemaic) or a sun-centered (Copernican) picture of reality can be made consistent with the motion of celestial bodies;
  • that goldfish physicists living in a curved bowl, though observing curved paths of motion of bodies that we observe as linear, could still formulate predictive laws governing motion as they see it;
  • that we cannot know whether we live in a simulated world, a virtual reality, one that the simulators rendered self-consistent.

Each of those world pictures is not only data-dependent, but is explanation-dependent.

In comparing different world pictures,

According to model-dependent realism, it is pointless to ask whether a model is real, only whether it agrees with observation. If there are two models that both agree with observation,...then one cannot say that one is more real than another. (pp. 45-46)

If two different models agree with the observations, to say that one gives a truer picture of reality than the other involves considerations outside model-independent reality, to consider possibly subjective matters such as which model may be the more convenient to employ in a given situation, the more elegant, the more intriguing, or otherwise appear more appealing.

It should be noted that Hawking/Mlodinow say (p. 7):

In the history of science we have discovered a sequence of better and better theories or models...Will this sequence eventually reach an end point,...or will we continue forever finding better theories, but never one that cannot be improved upon? We do not yet have a definitive answer to this question,...

which raises the prospect that an ultimate world picture of "reality" might be approachable, though perhaps never reached.

Some find the ambiguity introduced by alternative equivalent world pictures to be a defect of the concept of model-dependent realism.[4] That position, however, is based upon outside criteria, and an example of such criteria is provided shortly.

It should be emphasized that there is no restriction that a model use only observable or measurable constructs. The alternatives:

Do unobservable theoretical entities such as quarks and gluons really exist in the physical world, as objective entities independent of human will, or exist merely as human constructions for their utility in organizing our experience and predicting future events?[5]

are addressed by Hawking/Mlodinow in their definition of a model as follows:

QCD [Quantum chromodynamics] also has a property called asymptotic freedom, which we referred to, without naming it, in Chapter 3. Asymptotic freedom means that the strong forces between quarks are small when the quarks are close together but increase if they are farther apart, rather as though they were joined by rubber bands. Asymptotic freedom explains why we don’t see isolated quarks in nature and have been unable to produce them in the laboratory. Still, even though we cannot observe individual quarks, we accept the model because it works so well at explaining the behavior of protons, neutrons, and other particles of matter [Emphasis added]. [6]

Therefore, the definition of a model adopts any unobservable constructs as aspects of the reality "created" by that model.[Note 1] With this interpretation of a model, the alternatives posed by Cao above[5] are confronted by the metaphysical position of model-dependent realism first by rejection of any posit of "objective" reality beyond world pictures or networks of world pictures that organize experience, and second, like the world pictures themselves, model-dependent realism accepts any unobservable entities in the models used by these world pictures as part of the reality included in model-dependent realism.


The "reality" of science, even when restricted to the interpretation of observations and measurements, has been much discussed. Pierre Duhem (1861-1916) held that a physical model is no more than an aid to memory,[7][Note 2] summarizing and classifying facts by providing a symbolic representation of them and, moreover, the facts of physical theory are to be distinguished from common sense and metaphysics. His views were further developed by W. V. O. Quine (1908-2000), who suggested "“our statements about the external world face the tribunal of sense experience not individually, but only as a corporate body”. It is impossible to test a scientific hypothesis in isolation, but only as part of a system. These two authors were much concerned with how a theory was coupled to concrete observation and measurement, and how it morphed with admission of new data.[8][9]

The evolution of science forms part of this discussion. For example, Thomas Kuhn connected changes in scientists' views of reality to "revolutions" in science and changes in "paradigms".[10] As an example, Kuhn suggested that the Copernican "revolution" replaced the views of Ptolemy not because of empirical failures, but because of a new "paradigm" that exerted control over what scientists felt to be the more fruitful way to pursue their goals. Such historical analysis goes beyond the concept of a world picture itself to critique competing world pictures, and to assess how changes in ways to evaluate a world picture affect its influence over the development of knowledge. One aspect in the assessment of competing theories is the pragmatic question of which criteria indicate a fruitful path forward.[Note 3] These matters belong to the fields sociology of science and cognitive science.[11]

The matter is made more complicated by attempts to extend observations of scientific practice to wider realms, including religious systems, in an attempt to compare them. A key author in this arena was Barbour who proposed an approach called critical realism.[12] The word "critical" refers to reflection and analysis. This broad extension lies outside the realm of model-dependent realism itself, and falls into a much vaguer and more tendentious arena.

Model assessment

Many world pictures or theories may be proposed, and the issue of comparing, ranking, and generally critiquing them arises.

For example, quantum mechanics, which is a world picture or theory describing (among other matters) atomic interactions using a mathematical model of Hilbert space, is commonly called incomplete, despite its experimental success, as it is "not accompanied by an interpretation that is widely convincing."[13] Steven Pinker discusses this question using several quotations, including one from Murray Gell-Mann that describes quantum theory as: "that mysterious, confusing discipline which none of us really understands but which we know how to use."[14] These reservations about quantum mechanics appear to seek something more than a world picture, what might be called physical intuition, or visualization.[Note 4]

Hawking/Mlodinov do not address the intuitive qualities of a world picture or theory, or scientists' personal opinions of them, but they do raise the question of what constitutes a good theory. They suggest a good theory has these characteristics,(p. 51[2]), compared in parentheses to the criteria of Colyvan:[15]

  1. It is elegant (Formal elegance; no ad hoc modifications)
  2. Contains few arbitrary or adjustable elements (Simplicity/Parsimony)
  3. Agrees with and explains all existing observations (Unificatory/Explanatory power)
  4. Makes detailed predictions about future observations that can disprove or falsify the model if they are not borne out. (Boldness/Fruitfulness: the emphasis by Colyvan is not only upon prediction and falsification, but also upon pregnancy for future work.)

Hawking/Mlodinov note that "If the modifications needed to accommodate new observations become too baroque, it signals the need for a new model."[16] Of course, judgment about what is 'baroque' is somewhat subjective.[17]

The features of a "good" theory have been debated for centuries, going back perhaps even earlier than Occam's razor,[Note 5] which often is taken as an attribute of a good theory.[Note 6] Occam's razor might fall under the heading of "elegant", the first item on the list. The last item on the list is related to the criterion proposed by Popper:[18]

It must be possible for an empirical scientific system to be refuted by experience. (p. 18)

Those among us who are unwilling to expose their ideas to the hazard of refutation do not take part in the game of science. (p. 280)

Richard Feynman also expressed this view: "Of course, relativity is deeper than this [referring to a simplistic statement] because we can make definite predictions with it."[19]

Five somewhat similar criteria were proposed by Kuhn as what he called "the shared basis for theory choice", a list selected "not because they are exhaustive, but because they are individually important and collectively sufficiently varied to indicate what is at stake."[20] Another list is discussed by Colyvan.[15]

These desiderata of a "good theory" allow a critique of different theories. Although the various lists of criteria for a good model are very similar, (those of Hawking/Mlodinow,[21] or Kuhn,[22] or Colyvan,[15] for example) and according to their various authors are widely acknowledged, they are only heuristic. Worrall points out "One reason why these criteria do not supply a choice algorithm is that in live cases of theory choice, and, in particular, during scientific revolutions, these different criteria seldom, if ever, tell in the same direction. Much later, once the revolutionary theory has been developed and improved, it may outscore its older rival on all counts - but this happens as a result of the revolution and therefore can't form its rationale."[23] Some argue, nonetheless, that "principles of comparison" may have a justification beyond mere general acceptance.[Note 7]

Unfortunately, even the most successful world picture of modern science, the Standard Model of particle physics, satisfies only the last of the Hawking/Mlodinov criteria. As said by Hawking/Mlodinov (p. 52[2]):

..many people view the "standard model" inelegant. contains dozens of adjustable parameters whose values must be fixed to match observations, rather than being determined by the theory itself.

The Standard Model fails the third criterion in not encompassing gravitation. Hawking/Mlodinov (p. 58[2]) deal with the failure of a theory to encompass all observations using the notion of a network of overlapping theories, each describing some observations and agreeing with one another where the theories overlap. To quote:(p. 58[2]):

No single theory within the network can describe every aspect of the universe... Though this situation does not fulfill the traditional physicists' dream of a single unified theory, it is acceptable within the framework of model-dependent realism.

Presumably, each theory or world picture included in a network provides concepts for a "model-dependent reality", though that reality is restricted to the domain of data to which it applies. Where these model-dependent realities overlap, multiple interpretations of reality are available of equal value.

Data collection

...the measuring device has been constructed by the observer, and we have to remember that what we observe is not nature in itself but nature exposed to our method of questioning.
—Werner Heisenberg, Physics and Philosophy[24]

The definition of a model given by Hawking/Mlodinow is pretty straightforward if one has in mind a particular set of data to explain. Either the model explains the data or it doesn't, and if two models explain the data differently, any claim for the concepts employed by either as more true of "reality" must be based upon criteria lying outside the reach of model-dependent reality, such as the desiderata for a "good" theory listed earlier.

The matter is less clear when one considers the selection of just what "data" must be explained. Our senses are limited, and we accept that we cannot see and hear everything that comprises reality.[25] So we supplement the senses, for example, by using a telescope or a microscope. Historically the issue arose as to whether such instruments deceived us, and gradually they have been accepted as extensions of our natural capacities.[26][27]

The gathering of "data" supplementing our senses has gone far beyond the primitive telescope to its modern version (for example, the Hubble telescope) and the microscope to its modern version (for example, the scanning tunneling microscope).[28][29] Today experiments may require expensive apparatus not available to all, involving observations not even interpretable by many. Examples are the colliders of high-energy physics,[30] and the sophisticated electronic image acquisition of modern astronomy, guided by elaborate computer processing and filtering.[Note 8] One might reasonably ask how well the acquisition of "data" is separated from the "theory" that explains how the acquisition process works, and that often suggests where to look for new "data".[Note 9] Communication and critique of results becomes restricted to a narrow audience of technically oriented specialists, and those outside this group become irrelevant. The process by which data is allowed into the theory influences what is incorporated into "reality".

The gathering of data is complicated by the limited access to these data-acquisition instruments, both in a required training that could be seen as indoctrination (not necessarily deliberate, but de facto),[Note 10] and in limitations upon who, and what investigations, are worthy to use the instruments, as determined by various funding agencies and corporate laboratories. Although censorship is not the motivation directing government and corporate support, a preoccupation with popular and/or commercially attractive projects draws resources and talent away from less conspicuous goals potentially of more significance to a comprehensive "reality".[Note 11] In effect, the expense and expertise of modern research result in blinkers.[31][32][33]

The analysis as well as the gathering of data is becoming more complicated as our very notion of thinking, even of mathematical proof, is modified by technology, for example, by computers. Theoretical predictions are made by computer simulations that perform calculations beyond human capacity. The concepts entering a model-based reality may be only implicit in a computer programmable code, in open-ended algorithms, and may not be concepts the human mind is aware of directly.[34]

To a limited degree, the shaping of "reality" based upon modeling of selected data is a public enterprise, with all the foibles that implies. The public does not engage reality at a specialized deeply technical level, but at a metaphoric level:

All theories have metaphorical dimensions...that give depth and meaning to scientific ideas, that add to their persuasiveness and color the way we see reality."[35]

An explicitly metaphoric public participation is "eco-consciousness".[36] Metaphorical involvement also is evident in arenas such as gene research and genetically altered organisms, and investigations of stem cells, where the public is actively engaged.[37] Another example is archaeology and the limitations exerted upon examination of burial sites.[38][39] In some cases public participation leads to simple clamor, as in the case of global warming.[40][41] This broad public engagement, frequently informed by vested interests and oversimplifications, facilitates manipulation by groups with their own objectives, similar to the censorship found in the times of Vesalius and Galileo although lacking some of that institutional authority.[42]

Although the above examples suggest an indictment of metaphor as a foible of public participation in shaping reality, public engagement in some form is necessary and desirable, and ultimately a goal of the entire enterprise.


  1. One might ask how arbitrary concepts enter this view of reality. For example, in electromagnetic theory one can introduce a vector and a scalar potential, neither of which is unique, and is free to choose an admixture of the two called a "gauge". Apparently then, one could view each different gauge as a feature of reality in one of a family of overlapping realities, all of which describe the same observations. A contrasting view is found in: Gorden N Fleming (2004). Martin Carrier, Gerald J. Massey, Laura Ruetsche, eds: Science at century's end: philosophical questions on the progress and limits. Pittsburgh University Press, p. 244. ISBN 0822958201. “But the gauge-independent formalism would delineate the aspects of the theory one could safely take seriously, the aspects one could tentatively invest with ontological content.” 
  2. [see ref: Duhem, Pierre. (1991 reprint of translation)] pp. 55-106:  What we would call models in the sense of Hawking/Mlodinov, Duhem seems not to have subsumed under the rubric of 'model', but has reserved that name for the more restricted notion of 'mechanical models' which, he scoffs, are a weakness of the English, who have exerted an effort in creating such models "often much greater than the one the Frenchman needs to make in order to understand in its purity the abstract theory, which it is claimed the model embodies." (p. 71)
  3. A discussion of the evolutionary process from Kuhn's standpoint is found at Bird, Alexander (Aug 11, 2011). Edward N. Zalta (ed.):Thomas Kuhn. The Stanford Encyclopedia of Philosophy (Summer 2011 Edition). Retrieved on 2011-11-18.
  4. Quoting Feynman about his creative process: "It is impossible to differentiate the symbols from the thing; but it is very visual. It is hard to believe it, but I see these things not as mathematical expressions but a mixture of a mathematical expression wrapped into and around, in a vague way, around the object. So I see all the time visual things associated with what I am trying to do." Silvan S. Schweber (1994). QED and the men who made it: Dyson, Feynman, Schwinger, and Tomonaga. Princeton University Press, p. 465. ISBN 0691033277.  A more technical description is provided by Adrian Wüthrich (2010). The Genesis of Feynman Diagrams. Springer, p.9. ISBN 9048192277. 
  5. Occam's razor, sometimes referred to as "ontological parsimony", is roughly stated as: Given a choice between two theories, the simplest is the best. This suggestion commonly is attributed to William of Ockham in the 14th-century, although it probably predates him. See Baker, Alan (February 25, 2010). Simplicity; §2: Ontological parsimony. The Stanford Encyclopedia of Philosophy (Summer 2011 Edition). Retrieved on 2011-11-14.
  6. Both Newton and Einstein stressed parsimony. See Hugh G. Gauch (2003). Scientific method in practice. Cambridge University Press, pp. 342 ff. ISBN 0521017084. 
  7. For further discussion of the appraisal of theories see, for example, W. Newton-Smith (1981). “Chapter V: TS Kuhn: from revolutionary to social democrat; §3: The five ways”, The Rationality of Science. Psychology Press, pp. 112 ff. ISBN 0415058775. “The fact that science is progressing in the sense of generating theories of greater verisimilitude provides reason for thinking that the methods employed (the principles of comparison) are in fact legitimate evidential principles.”  The four desiderata of a good model by Hawking/Mlodinov are expressed differently as "the five ways", a partial list of principles of comparison attributed to Kuhn, author of a well known book (called one of the most influential books since WW II by The Times Literary Supplement) Thomas S Kuhn (1966). The structure of scientific revolutions, 3rd ed. University of Chicago Press. ISBN 0226458083. .
  8. Most telescopic images are collected today using the charge-coupled device or CCD, and computer processed. See, for example, Steve B. Howell (2006). Handbook of CCD astronomy, Volume 5 of Cambridge observing handbooks for research astronomers; 2nd ed. Cambridge University Press. ISBN 0521617626.  In addition, the telescope itself is aimed and adjusted using computer programs.
  9. "Scientific fact and theory are not categorically separable." Thomas S Kuhn (2008). Francis Wilson Smith, Thomas Bender (eds.): American higher education transformed, 1940-2005: documenting the national discourse, Reprint of The structure of scientific revolutions (1966). John Hopkins University Press, p. 243. ISBN 0226458083. 
  10. Kuhn refers to this preparation as "educational initiation that prepares and licenses the student for professional practice"...[that comes] " exert a deep hold on the scientific mind." Thomas S Kuhn (1966). The structure of scientific revolutions, 3rd ed. University of Chicago Press, p. 5. ISBN 0226458083. 
  11. For example, even in the very liberal environment of Bell Laboratories engaged in "fundamental research", experiments following discovery of the cosmic background radiation by Arno Penzias and Robert Woodrow Wilson were frowned upon. As Wilson gently recalled matters: "local management here decided that we had had our fun doing astronomy and that now we really ought to contribute something to the telephone company too". Quoted in Jeremy Bernstein (1987). “Chapter 14: Robert Wilson”, Three degrees above zero: Bell Laboratories in the information age. Cambridge University Press, p. 208. ISBN 0521329833.  Likewise, much of the research underlying the modern integrated circuit had to be conducted in the wee hours of the morning, so as not to interfere with "important" corporate research. See for example, Michael Riordan, Lillian Hoddeson (1997). Crystal fire: the birth of the information age. W. W. Norton & Company, p. 179. ISBN 0393041247. “But because they could not get even a small laboratory dedicated to them, they put it [their crystal-pulling apparatus] on a set of wheels so that it could be rolled into and out of a storage closet in the metallurgical lab. Working on their own time,..., they managed to "bootleg" their crystal growing program into existence.”  Corporate official "history" has glossed over these problems to present a view of great wisdom and encouragement.


  1. Khlentzos, Drew (February 2011). Edward N. Zalta (ed.):Challenges to Metaphysical Realism. The Stanford Encyclopedia of Philosophy (Spring 2011 Edition). Retrieved on 2011-11-19.
  2. 2.0 2.1 2.2 2.3 2.4 Hawking SW, Mlodinow L. (2010). The Grand Design, Kindle edition. New York: Bantam Books. ISBN 978-0-553-90707-0. 
  3. 3.0 3.1 Hawking SW, Mlodinow L.. “Chapter 3: What is reality?”, cited work, pp. 42-43. ISBN 0553805371. 
  4. This argument is attributed to Thomas Kuhn in Tian Yu Cao (2010). From Current Algebra to Quantum Chromodynamics: A Case for Structural Realism. Cambridge University Press, p. 4. ISBN 0521889332. 
  5. 5.0 5.1 This question is a close paraphrase of a statement in Tian Yu Cao (2010). From Current Algebra to Quantum Chromodynamics: A Case for Structural Realism. Cambridge University Press, pp. 2-3. ISBN 0521889332. 
  6. See above reference: Hawking SW, Mlodinow L. (2010). “Chapter 5: The theory of everything”, The Grand Design, p. 110. ISBN 978-0-553-90707-0. 
  7. Duhem, Pierre. (1991). The Aim and Structure of Physical Theory, Princeton Science Library. Vol. 13 of Atheneum Paperbacks; reprint in translation of La théorie physique, 2nd edition of 1914. Princeton University Press. ISBN 069102524X.. 
  8. Roger Ariew (2011). Edward N. Zalta ed.:Pierre Duhem. The Stanford Encyclopedia of Philosophy (Spring 2011 edition). Retrieved on 2011-08-26.
  9. Peter Hylton (2010). Edward N. Zalta ed.:Willard van Orman Quine. The Stanford Encyclopedia of Philosophy (Fall 2010 Edition). Retrieved on 2011-08-26.
  10. Thomas S Kuhn (1966). The structure of scientific revolutions, 3rd ed. University of Chicago Press. ISBN 0226458083. 
  11. Ronald N. Giere (2011). “§5.4 Cognitive science and the sociology of science”, Seymour Mauskopf, Tad Schmaltz (eds): Integrating History and Philosophy of Science: Problems and Prospects, Boston studies in the philosophy of science #263. Springer, pp. 62 ff. ISBN 940071744X. 
  12. Niels Henrik Gregersen (2004). “Chapter 4: Critical realism and other realisms”, Robert J. Russell, ed: Fifty years in science and religion: Ian G. Barbour and his legacy. Ashgate Publishing, Ltd, pp. 78 ff. ISBN 075464118X. 
  13. Gordon N Fleming (2004). “Limits and the future of quantum theory”, Martin Carrier, Gerald J. Massey, Laura Ruetsche, eds: Science at century's end: philosophical questions on the progress and limits of science. University of Pittsburgh Press, pp. 237 ff. ISBN 0822958201. 
  14. Steven Pinker (2003). The blank slate: the modern denial of human nature. Penguin, p. 347. ISBN 0142003344. 
  15. 15.0 15.1 15.2 Mark Colyvan (2001). The Indispensability of Mathematics. Oxford University Press, pp. 78-79. ISBN 0195166612. 
  16. See The Grand Design, p. 53
  17. For example, see these two extensive discussions of applying the criterion of 'simplicity': Simon Fitzpatrick (April 5, 2013). Simplicity in the Philosophy of Science. Internet Encyclopedia of Philosophy. and Baker, Alan (Feb 25, 2010). Edward N. Zalta, ed:Simplicity. The Stanford Encyclopedia of Philosophy (Summer 2011 Edition).
  18. Karl Raimund Popper (2002). The logic of scientific discovery, Reprint of translation of 1935 Logik der Forchung. Routledge/Taylor & Francis Group, p. 18, p. 280. ISBN 0415278430. 
  19. Richard Phillips Feynman (2011). Robert B. Leighton, Matthew Sands, eds: The Feynman Lectures on Physics, Vol. I, Millennium edition. Basic Books, p. 16-1. ISBN 0465024939. 
  20. Thomas S Kuhn (2007). “Chapter 10: Objectivity, Value Judgement and Theory Choice”, Marc Lange (ed.): Philosophy of science: an anthology, Reprint of 1977 paper in The Essential Tension. Wiley-Blackwell. ISBN 1405130342. 
  21. See The Grand Design, p. 51
  22. Thomas Kuhn (1977). "The Essential Tension: Selected Studies in Scientific Tradition and Change": 321-322. On-line excerpt stating his criteria is found here and they also are discussed by Bird, Alexander (Aug 11, 2011). Edward N. Zalta, ed:Thomas Kuhn. The Stanford Encyclopedia of Philosophy (Spring 2013 Edition).
  23. John Worrall (1990). “Scientific revolutions and scientific rationality”, C Wade Savage, ed: Scientific theories; Volume 14 of Minnesota Studies in the Philosophy of Science. University of Minnesota Press. ISBN 0816618011. 
  24. Werner Heisenberg (2007). “Chapter III: The Copenhagen interpretation of quantum theory”, Physics and Philosophy: The Revolution in Modern Science, Reprint of Harper & Row 1962 ed. New York: Harper Perennial Modern Classics, p. 58. ISBN 0061209198. 
  25. Richard Dawkins (2011). The Magic of Reality: How We Know What's Really True. Free Press, p. 13. ISBN 1439192812. “But are we only going to call something "real" if we can detect it with one of our five senses?...Obviously we can enhance our senses through the use of special instruments...” 
  26. Initially, many refused to believe the results of the telescope. Kepler wrote to Galileo that such persons were "stuck in a world of paper" , blind not by force of circumstance but of their own foolish will. Dan Hofstadter (2009). “Chapter 2: The telescope; or seeing”, The Earth Moves: Galileo and the Roman Inquisition. W W Norton & Co, pp. 53 ff. ISBN 978-0-393-06650-0. 
  27. Cautions abound concerning the deceptive nature of the microscope. For example, see Hermann Schacht (1855). The microscope: and its application to vegetable anatomy and physiology, 2nd ed. S. Highley, p. 57. “Seeing, as Schleiden justly observes, is a difficult art, and seeing with the microscope is yet more difficult...” 
  28. Hubble space telescope. NASA. Retrieved on 2011-07-30.
  29. The scanning tunneling microscope. Retrieved on 2011-07-30.
  30. The large hadron collider. CERN. Retrieved on 2011-07-26.
  31. Derek J.De Solla Price (1986). Little Science, Big Science and beyond. Columbia University Press. ISBN 0231049560. 
  32. Lee Smolin (2007). “Chapter 16: How do you fight sociology”, The trouble with physics: the rise of string theory, the fall of a science, and what comes next. Houghton Mifflin Harcourt, pp. 261 ff. ISBN 061891868X. 
  33. Peter Woit (2006). “Chapter 16: The only game in town: the power and the glory of string theory”, Not even wrong: the failure of string theory and the search for unity in physical law. Basic Books, pp. 221 ff. ISBN 0465092756. 
  34. Timothy R. Colburn (2000). “Chapter 6: Models of the mind”, Philosophy and computer science. ME Sharpe, Inc., pp. 68 ff. ISBN 156324991X. 
  35. Brian Goodwin (2001). “The myth behind the metaphors”, How the Leopard Changed Its Spots: The Evolution of Complexity, Reprint with a new preface of 1994 ed. Princeton University Press, p. 33. ISBN 0691088098.  Title links to Google Books preview.
  36. Larson B (2011). Metaphors for Environmental Sustainability: Redefining Our Relationship with Nature. Yale University Press. ISBN 9780300151534..  Science magazine book review.
  37. Gregory Pence (2007). “Chapter 7: Recreating nature: Patenting human genes?”, Re-Creating Medicine: Ethical Issues at the Frontiers of Medicine. Rowman & Littlefield, pp. 137 ff. ISBN 084769691X. 
  38. David Hurst Thomas (2001). Skull Wars: Kennewick Man, Archaeology, and the Battle for Native American Identity. Basic Books. ISBN 046509225X. 
  39. Robert L. Kelly, David Hurst Thomas (2009). Archaeology, 5th ed. Cengage Learning, p. xxxiii. ISBN 0495602914. “How can we pursue this laudable goal if the very act of conducting research offends the living descendents of the ancient people being studied?” 
  40. For a discussion by a proponent of intelligent design, see for example Roy W. Spencer (2010). Climate Confusion: How global warming hysteria leads to bad science, pandering politicians and misguided policies that hurt the poor, Paperback version of 2008 ed. Encounter Books. ISBN 1594033455. 
  41. James Hoggan, Richard D. Littlemore (2009). Climate cover-up: the crusade to deny global warming. Greystone Books. ISBN 1553654854. 
  42. Andrew Dickson White (1896). A history of the warfare of science with theology in Christendom, Volume 2. D. Appleton & Co..