With its strategic consideration of phenomenal consciousness illusorily seeming to us, illusionism claims to deny phenomenality and thereby obviate the hard problem of consciousness. The problem with illusionism, however, is that, although its thesis appears persuasively simple, it strikes as absurd insofar as the phenomenal illusions themselves also seem as much as phenomenality, keeping no fundamental differences between the two. In short, it reinforces the same phenomenon/issue, i.e., phenomenality, that it claims to deny/avoid. This single absurdity is reflective of its (...) self-refuting nature, and it alone is enough for a rejection of illusionism. However, does illusionism have any reasonable justification to defend itself in the face of the experientially undeniable reality of phenomenal consciousness? This paper attempts to find out if there is any such illusionist justification. (shrink)

There seems to exist a dilemma in the literature as to the correct relativistic formula for the Sagnac phase-shift. The paper addresses this issue in the light of a novel, kinematically equivalent linear Sagnac-type thought experiment, which provides a vantage point from which the effect of rotation in the usual Sagnac effect can be analyzed. The question is shown to be related to the so-called rotating disc problem known as the Ehrenfest paradox. The relativistic formula for the Sagnac phase-shift seems (...) to depend on the way the paradox is resolved. Kinematic resolution of the Ehrenfest paradox proposed by some authors predicts the usually quoted formula for the Sagnac delay but the resolution itself is shown to be based upon some implicit assumptions regarding the behaviour of solid bodies under acceleration. In order to have a greater insight into the problem, a second version of the thought experiment involving linear motion of a “special type” of a non-rigid frame of reference is discussed. It is shown by analogy that the usually quoted special relativistic formula for the Sagnac delay follows, provided the material of the disc matches the “special type.”. (shrink)