B-theory of time

From Wikipedia, the free encyclopedia
  (Redirected from B-Theory of time)
Jump to: navigation, search

The B-theory of time is a metaphysical philosophy of time. The theory is noted somewhat due to the support of the theory from the physics community as opposed to other philosophical hypotheses (e.g A-theory of time).


A-theory and B-theory of time, is derived from the analysis of time and change developed by Cambridge philosopher J. M. E. McTaggart in 'The Unreality of Time' (1908), in which events are ordered via a tensed A-series or a tenseless B-series. A-series is closely related to presentism while B-series is closely related to eternalism. Events (or 'times'), McTaggart observed, may be characterized in two distinct, but related, ways. On the one hand they can be characterized as past, present or future, normally indicated in natural languages such as English by the verbal inflection of tenses or auxiliary adverbial modifiers. Alternatively events may be described as earlier than, simultaneous with, or later than others. Philosophers are divided as to whether the tensed or tenseless mode of expressing temporal fact is fundamental. Those who (like Arthur Prior1) take the tensed notions associated with the past, present and future to be the irreducible foundations of temporality and our conceptions of temporal fact, are called A-theorists (similar to presentists). A-theorists deny that past, present and future are equally real, and maintain that the future is not fixed and determinate like the past. A-theorists also believe that a satisfactory account of time must acknowledge a fundamental metaphysical difference between past, present and future (Prior 2003). Those who wish to eliminate all talk of past, present and future in favour of a tenseless ordering of events are called B-theorists. B-theorists (such as D.H. Mellor2 and J.J.C. Smart3) believe that the past, the present, and the future are equally real.

The past, the present, and the future feature very differently in deliberation and reflection. We remember the past and anticipate the future, for example, but not vice versa. B-theorists maintain that the fact that we know much less about the future simply reflects an epistemological difference between the future and the past: the future is no less real than the past; we just know less about it (Mellor 1998). A view was held, for example by Quine and Putnam, that physical theories such as special relativity and latterly Quantum mechanics provide the B-theory with compelling support.45 The difference between A-theorists and B-theorists is often described as a dispute about temporal passage or 'becoming' and 'progressing'. B-theorists argue that this notion is purely psychological and not epistemological, and embodies serious confusion about time, while many A-theorists argue that in rejecting temporal 'becoming', B-theorists reject time's most vital and distinctive characteristic. It is common (though not universal) to identify A-theorists' views with belief in temporal passage.

Description of B-theory

The B-theory of time has support from physics as it is somewhat grounded in scientific reasoning. In special relativity, the relativity of simultaneity implies there is not a unique present. Many of special relativity's counter-intuitive predictions such as length contraction and time dilation are a result of this. Experimental confirmation of both effects include the time dilation of moving particles and shifts in the atomic clocks of satellites in orbit. Relativity of simultaneity implies a block universe where the present for different observers is a time slice of the four dimensional universe. Thus it is also common (though not universal) for B-theorists to be four-dimensionalists, that is, to believe that objects are extended in time as well as in space and therefore have temporal as well as spatial parts. This is sometimes called a time-slice ontology (Clark, 1978). This theory of time is depicted in the movie Interstellar. The physics of Interstellar was based on the work of renowned physicist Kip Thorne.6 Astronaut Cooper enters a black hole that is a closed time-like curve, which allows him to transmit information back to a time in his perceived past. According to the B-theory of time, this is consistent and does not induce a paradox.


While supported by the scientific community, William Craig, a theologian philosopher, argues that the B-theory of time is burdened with heavy philosophical problems. For example, that temporal becoming is an entirely subjective phenomenon, and hence not an objective feature of reality. In the absence of minds, every temporal moment and event simply exists tenselessly; there are no tensed facts; no past, present, or future; nothing comes into existence or happens except in the tenseless sense of existing at certain appointed stations as opposed to others.7


  1. ^ (French) http://hylo.loria.fr/content/papers/files/tense.pdf
  2. ^ "Philosophy Cambridge Mellor Time Tense". People.pwf.cam.ac.uk. Retrieved 2014-03-03. 
  3. ^ "Google Drive Viewer". Docs.google.com. Retrieved 2014-03-03. 
  4. ^ "Time-slices of particular continuants as basic individuals: An impossible ontology - Springer". Springerlink.com. 1978-05-01. Retrieved 2014-03-03. 
  5. ^ "Google Drive Viewer". Docs.google.com. Retrieved 2014-03-03. 
  6. ^ "New 'Interstellar' Trailer Goes Deep; Plus Kip Thorne Featurette". /Film. October 1, 2014. Retrieved October 5, 2014. 
  7. ^ Craig, William Lane (2000). The tenseless theory of time : a critical examination. Dordrecht [u.a.]: Kluwer Acad. Publ. ISBN 978-0792366355. 


  • Clark, M. (1978) 'Time-slices of particular continuants as basic individuals: An impossible ontology'. Philosophical Studies 33, 403--408.
  • Davies, Paul (1980) Other Worlds. Harmondsworth: Penguin.
  • McTaggart, J.M.E. (1908) 'The Unreality of Time', Mind 17: 457-73.
  • McTaggart, J.M.E. (1927) The Nature of Existence, Vol II. Cambridge: Cambridge University Press.
  • Mellor, D.H. (1998) Real Time II. London: Routledge.
  • Prior, A.N. (2003) Papers on Time and Tense. New Edition by Per Hasle, Peter Øhrstrøm, Torben Braüner & Jack Copeland. Oxford: Clarendon.
  • Putnam, H. (2005) 'A Philosopher Looks at Quantum Mechanics Again', British Journal for the Philosophy of Science, 56, pp 615 - 634.
  • Quine, W. V. O. (1960) Word and Object, Cambridge, MA: M.I.T. Press.

External links

  • Markosian, Ned, 2002, "Time", Stanford Encyclopedia of Philosophy
  • Arthur Prior, Stanford Encyclopedia of Philosophy

Return to Fuhz Home - This article covering B-Theory of time is enhanced for the visually impaired.
This page uses content from Wikipedia. Original artice from http://en.wikipedia.org/wiki/B-Theory_of_time
The text of this Fuhz article is released under the GNU Free Documentation License

Valid XHTML 1.0 Transitional Valid CSS!

Privacy Policy