Time is still the great mystery to us. It is no more than a concept; we don't know if it even exists.
Clifford D. SimakAnd time itself? Time was a never-ending medium that stretched into the future and the past - except there was no future and no past, but an infinite number of brackets, extending either way, each bracket enclosing its single phase of the Universe.
Clifford D. SimakMy reluctance to use alien invasion is due to the feeling that we are not likely to be invaded and taken over. It would seem to me that by the time a race has achieved deep space capability it would have matured to a point where it would have no thought of dominating another intelligent species. Further than this, there should be no economic necessity of its doing so. By the time it was able to go into deep space, it must have arrived at an energy source which would not be based on planetary natural resources.
Clifford D. SimakThis is written in the elder days as the Earth rides close to the rim of eternity, edging nearer to the dying Sun, into which her two inner companions of the solar system have already plunged to a fiery death. The Twilight of the Gods is history; and our planet drifts on and on into that oblivion from which nothing escapes, to which time itself may be dedicated in the final cosmic reckoning.
Clifford D. Simak