There is a strange faith among theoreticians and philosophers of science: all theories, past, present and future, are false (pessimistic induction) but new theories are somehow less false than old ones:

http://cdn.preterhuman.net/texts/tho...%20science.pdf
W.H. Newton-Smith, THE RATIONALITY OF SCIENCE, 1981, p. 14: "...all physical theories in the past have had their heyday and have eventually been rejected as false. Indeed, there is inductive support for a pessimistic induction: any theory will be discovered to be false within, say 200 years of being propounded. (...) Indeed the evidence might even be held to support the conclusion that no theory that will ever be discovered by the human race is strictly speaking true. (...) The rationalist (who is a realist) is likely to respond by positing an interim goal for the scientific enterprise. This is the goal of getting nearer the truth. In this case the inductive argument outlined above is accepted but its sting is removed. For accepting that argument is compatible with maintaining that CURRENT THEORIES, while strictly speaking false, ARE GETTING NEARER THE TRUTH."

The new-theories-are-less-false faith is incompatible with deductivism. Consider Einstein's 1905 speed-of-light (second) postulate:

http://www.fourmilab.ch/etexts/einstein/specrel/www/
"...light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body."

Let us assume that the first postulate, the principle of relativity, is true. Then we have the following situation related to the fact that the theory (special relativity) is deductive: If the speed-of-light (second) postulate is true, and if the arguments of the theory are valid, then all the propositions of the theory (which are consequences of the postulates) are true, and IN THIS SENSE the theory is absolutely true. No degrees of falsehood are allowed.

If Einstein's 1905 speed-of-light postulate is false, that is, if the speed of light does depend on the speed of the emitting body, then it is easy to show that the equation c'=c+v given by Newton's emission theory of light and showing how the speed of light varies with v, the speed of the emitter relative to the observer, is true:

http://www.philoscience.unibe.ch/doc...S07/Norton.pdf
John Norton: "These efforts were long misled by an exaggeration of the importance of one experiment, the Michelson-Morley experiment, even though Einstein later had trouble recalling if he even knew of the experiment prior to his 1905 paper. This one experiment, in isolation, has little force. Its null result happened to be fully compatible with Newton's own emission theory of light. Located in the context of late 19th century electrodynamics when ether-based, wave theories of light predominated, however, it presented a serious problem that exercised the greatest theoretician of the day."

http://books.google.com/books?id=JokgnS1JtmMC
"Relativity and Its Roots" By Banesh Hoffmann, p.92: "Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether."

http://philsci-archive.pitt.edu/1743/2/Norton.pdf
John Norton: "In addition to his work as editor of the Einstein papers in finding source material, Stachel assembled the many small clues that reveal Einstein's serious consideration of an emission theory of light; and he gave us the crucial insight that Einstein regarded the Michelson-Morley experiment as evidence for the principle of relativity, whereas later writers almost universally use it as support for the light postulate of special relativity. Even today, this point needs emphasis. The Michelson-Morley experiment is fully compatible with an emission theory of light that CONTRADICTS THE LIGHT POSTULATE."

The respective Newtonian theory (validly deducible from the principle of relativity (first postulate) and the equation c'=c+v (second postulate) is absolutely true in the sense that all its propositions are true. Again, no degrees of falsehood are allowed.

Clearly in DEDUCTIVE science the new-theories-are-less-false faith is unjustified. The transition from Newtonian to relativistic mechanics was either a transition from absolutely false to absolutely true or a transition from absolutely true to absolutely false.

Pentcho Valev