BY ARTURO SANGALLI
SPECULATIONS AND THEORIES ABOUT THE EXISTENCE of other worlds have a long history. In recent times, the arguments have shifted away from their typical philosophical and theological character to supposedly become more objective thanks to their scientific underpinnings. A prime example of this trend is the current multiverse theory, which has the support of a number of famous cosmologists, for example, Max Tegmark. But are these arguments more credible than counterarguments based on philosophical and metaphysical considerations?