The Last Question - Plot Summary

Plot Summary

The last question was asked for the first time, half in jest, on May 21, 2061, at a time when humanity first stepped into the light. The question came about as a result of a five dollar bet over highballs, and it happened this way ... —Opening line, The Last Question

The story deals with the development of computers called Multivacs and their relationships with humanity through the courses of seven historic settings, beginning in 2061. In each of the first six scenes a different character presents the computer with the same question; namely, how the threat to human existence posed by the heat death of the universe can be averted. The question was: "How can the net amount of entropy of the universe be massively decreased?" This is equivalent to asking: "Can the workings of the second law of thermodynamics (used in the story as the increase of the entropy of the universe) be reversed?" Multivac's only response after much "thinking" is: "INSUFFICIENT DATA FOR MEANINGFUL ANSWER."

The story jumps forward in time into newer and newer eras of human and scientific development. In each of these eras someone decides to ask the ultimate "last question" regarding the reversal and decrease of entropy. Each time, in each new era, Multivac's descendant is asked this question, and finds itself unable to solve the problem. Each time all it can answer is an (increasingly sophisticated, linguistically): "THERE IS AS YET INSUFFICIENT DATA FOR A MEANINGFUL ANSWER."

In the last scene, the god-like descendant of humanity (the unified mental process of over a trillion, trillion, trillion humans that have spread throughout the universe) watches the stars flicker out, one by one, as the universe finally approaches the state of heat death. Humanity asks AC, Multivac's ultimate descendant, which exists in hyperspace beyond the bounds of gravity or time, the entropy question one last time, before humanity merges with AC and disappears. AC is still unable to answer, but continues to ponder the question even after space and time cease to exist. Eventually AC discovers the answer, but has nobody to report it to; the universe is already dead. It therefore decides to show the answer by demonstrating the reversal of entropy, creating the universe anew. The story ends with AC's pronouncement,

And AC said: "LET THERE BE LIGHT!" And there was light-- —Closing line, The Last Question

Answers from Multivac

Throughout the story, the answer given by Multivac changes, albeit slightly, yet refined after each iteration. The first answer was simply five words, "INSUFFICIENT DATA FOR MEANINGFUL ANSWER".

When Jerrodd, Jerrodine, and Jerrodette 1 and 2 asked in the second section, the answer refined to "INSUFFICIENT DATA FOR A MEANINGFUL ANSWER.", increasing to 6 words.

VJ-23X and MQ-17J contemplating the similar, Multivac stated: "THERE IS INSUFFICIENT DATA FOR A MEANINGFUL ANSWER", totaling to 8 words.

With Zee Prime and Dee Sub Wun asking the same, the response was "THERE IS AS YET INSUFFICIENT DATA FOR A MEANINGFUL ANSWER.", expanding to 10 words.

Humans asked as separate beings, and again as an entire consciousness, and were given the same response of "THERE IS AS YET INSUFFICIENT DATA FOR A MEANINGFUL ANSWER." The last time it was asked, it was the last question it needed to answer, and thus, Multivac spent its remainder of time solving the question.