2017-05-16 20:50:53 UTC
In this short story, probably 60s or so, there is a treasure trove of alien artifacts on a planet. Access is controlled by a powerful robot. Many have tried to impersonate the owners. The robot will ask a series of questions, and if the person gets one wrong they are killed. Some sort of sinuous blade emerges from the robot or something like that.
The protagonist and his partner prepared or obtained a small computer with all the knowledge. The partner attempts entry, but after a series of correct answers is still killed. The protagonist, in desperation decides to try anyway. He asks the robot what he must do, and the answer is something along the lines of demonstrate truth. He then answers every question with random utterances. He is granted admission.
While gathering some items to take in the first wave, the robot idly inquires as to why he selected those. He answers something complimentary about the items. He realizes that he has given a relevant answer to the question, as the blade begins to emerge.