“If all questions were answered, all riddles solved, every fold unfolded, every wrinkle in the fabric of the Universe smoothed—the greatest and noblest game in the Universe would be ended, and there would be nothing left for the mind to do but console itself with trivia. Unbearable! MAY X ALWAYS BE WITH US TO AFFORD US PLEASURE!”—Isaac AsimovAsimov is once again at his best: exploring, inspiring, hypothesizing, and teaching. Whether he’s imagining a world in which silicon molucules would serve as the basis for life, speculating on the limits (in both directions) of the electromagnetic spectrum, or simply fiddling around with algebraic equations, Asimov presents his characteristically brilliant essays on physics, chemistry, mathematics, and astronomy with the wit and wisdom that have made him the most popular writer of science today.“ASIMOV PRACTICES WITH HIGH GOOD HUMOR AND BRASH PLEASURE THE ROLE OF INFORMAL EXPLAINER-AT-LARGE TO THE UNIVERSE.”—The Wall Street Journal