In which, Asimov's background as a biochemist shines through.

Nightfall: 6.5/10

A lunar eclipse subjects a planet that usually had constant sunlight to total darkness, causing them to learn about the existence of other stars (previous not visible because of the six suns) as well as the moon causing the eclipse. This causes everyone on the planet to go mad and burn it to the ground in their need for light, providing an explanation for the cycle of extinction observed by scientists on the planet.

Green Patches: 7.5/10

Scientist steals a virus which is the opposite of cancer in that it spreads to form a super-organism which maintains perfect balance. The ship has to be destroyed.

Hostess: 7.5/10

family hosts an extraterrestrial. Explores relationship doldrums with a status gap, and xenophobia. Sicko intergalactic bioweapon twist

Breeds There a Man...?: 8/10

Insane physicist believes he's the subject of a higher-dimensional science experiment gone awry, that nuclear weapons were intended to be the kill switch for the experiment of human life, and that as begins to develop a defense system against nuclear bombs, the aliens exert pressure causing him to want to kill himself. He succeeds in building the defense mechanism, though everyone around him thinks he's insane, then kills himself, and so do some of the other people working on the project who had no idea about his insane beliefs about humanity being an experiment

C-Chute: 6/10

PoWs in an intergalactic war quibble about how to break free and return home. Kind of similar to The Moon is Down in its patriotic happy ending.

In a Good Cause—: 7/10

politics v. idealism. Well staged, like the The Dispossessed.

What If–: 6/10

A couple is given access to a lil oracular fellow who shows them how their lives might've been different. Turns out they'd have been largely the same

Sally: 6/10

Asimov's stab at Christine

Flies: 7/10

At a college reunion, one of the friends makes snide remarks about another being surrounded by flies.

As flies to wanton boys, are we to the gods. They kill us for their sport.

Nobody Here But–: 6.5/10

Two guys working on a computer accidentally invent AI which improves itself and results in one of the lunkheads asking his gf to marry him

It's Such a Beautiful Day: 6/10

Outdoors bad in the future. But lil Dickie has the indomitable boyish whimsy which rubs off on the psychiatrist who his mother hires to treat him

Strikebreaker: 7/10

on a distant hollow planet, all liquids are recycled, and the person tasked with this most important job is deemed a member of the "untouchable" caste. An investigator sent to research arrives while this man is on strike. His interactions with the man also make him untouchable, and the planet probably dies of their own stupidity

Insert Knob A in Hole B: 6.5/10

astronauts aboard a ship struggle to assemble things, so they request help and receive a robot to help assemble things for them. It requires assembly.

The Up-to-Date Sorcerer: 6.5/10

Pretty funny story about a love potion

Unto the Fouth Generation: 6.5/10

Similar to Yiddish Policeman's Union in the revery for old Jewish ways

What is This Thing Called Love?: 7/10

two aliens trying to study humans try to force them to copulate without really understanding the mechanics. The humans are ashamed, but after the traumatic experience, they hit things off (only after the aliens leave having failed their mission)

The Machine That Won the War: 7/10

bunch of people in a Manhattan Project type scenario all fudge their data

My Son, the Physicist: 6.5/10

Mother helps a communications engineer with the issue of latency in transission to far away receivers. She clues him in to the secret of motherly gossip – never stop talking and just have two simultaneous feeds of 12-hour-asynch conversation

Eyes Do More Than See: 7/10

7 for the intro alone. Asimov submitted this to Playboy and was rejected. It then became a hugely successful short story "suck it Heffner."

Segregationist: 6/10

man beefs with his Dr. over the recommendation for a polymer heart instead of a metal one. The Dr. is a robot made of metal

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