Blish trained as a biologist at Rutgers and Columbia University, and spent 1942-1944 as a medical technician in the U.S. Army. After the war he became the science editor for the Pfizer pharmaceutical company. His first published story was in 1940, and his writing career progressed until he gave up his job to become a professional writer. Perhaps his most famous works were the 'Okies' stories in Astounding Science Fiction, known collectively as the 'Cities in Flight'. The framework for these was set in the novel They Shall Have Stars. This shows the development of the two essential features of the series. The first was the development of the anti-ageing drug ascomycin - Blish's employer Pfizer makes a thinly disguised appearance in a section showing the screening of biological samples for interesting activity. (they also appear in disguise as one of the sponsors of the polar expedition in Fallen Star) The second was the development of an antigravity device known as the 'spindizzy'. Since the device became more efficient as its field of influence was increased, entire cities were lifted from Earth and sent roving amongst the stars. The stories were pure space opera, and could have continued as a series indefintely, were it not for Blish setting the end of the Universe in 4004 AD (the chronology in early editions of They Shall have Stars differed somewhat from the later reprints, showing that this had not been planned by Blish at the beginning of the series)
Another group of novels were (apparently retrospectively) declared by Blish to be a trilogy: each dealing with an aspect of the price of knowledge, and given the overall name by Blish of 'After such knowledge' (the title taken from a quote from T.S. Eliot). The first, A Case of Conscience (a winner of the 1959 Hugo award), showed a Jesuit priest confronted with an alien intelligent race, apparently unfallen, which he eventually concludes must be a satanic fabrication. The second, Doctor Mirabilis is an historical novel about the medieval proto-scientist Roger Bacon. The third, actually two very short novels, Black Easter and The Day after Judgement were written using the assumption that the ritual magic for summoning demons as described in grimoires actually worked. In the first book, a wealthy arms manufacturer comes to a black magician with a strange request: he wishes to release all the demons from hell for one night to see what might happen. The book mainly consists of a lengthy description of the summoning ritual, and the grotesque figures of the demons as they appear. The book ends with Baphomet announcing to the participants that the demons can not be compelled to return to hell: the War is over, and God is dead. The Day After Judgment shows the characters from the first book, and the realisation that God may not be dead, as something appears to be restraing the actions of the demons upon Earth.
Of Blish's short stories, his most famous are the 'Pantropy' stories (collected in The Seedling Stars), in which humans are modified to live in various alien environments, this being easier and vastly cheaper than terraforming. The most popular of this series was Surface Tension, in which generations of aquatic humans battle with the other occupants of their world, eventually building a space ship to cross to other worlds - at the climax of the story, the two-inch long wooden spacecraft trundles along on caterpillar treads to the next puddle(!)
Blish collaborated with Norman L. Knight on a series of stories set in a world with a population a thousand times that of today, and followed the efforts of those keeping the system running, collected in one volume as A Torrent of Faces
Cities in Flight:
- They Shall Have Stars 1957 (also published under the title Year 2018!)
- A Life for the Stars
- Earthman Come Home (1956)
- A Clash of Cymbals (1959)
After Such Knowledge:
- A Case of Conscience - the first section published in Worlds of If, 1953, expanded version published 1958
- Doctor Mirabilis (1964)
- Black Easter or Faust Aleph-null (serialised as `Faust aleph-null' in Worlds of If, 1970)
- The Day After Judgement (published in Galaxy magazine in 1970, book publication 1972)
- The Seedling Stars (1957)
- The Night Shapes
- Jack of Eagles
- Welcome to Mars!
- Fallen Star (1957) - Set in the International Geophysical Year of 1958, it tells the story of a disaster-ridden polar expedition that finds a meterorite containing fossil life forms.
- The Quincunx of Time
- Mission to the Heartstars
- Titans' Daughter (also under the title `Beanstalk')
- A Torrent of Faces (with Norman L. Knight, 1967)
- Midsummer Century
- Star Trek 1-11 (1967-1975) Novelizations of the scripts of the well-known TV series.
- Spock Must Die (1975) An original Star Trek novel.
Blish wrote criticism of science fiction (some quite scathing) under the name of William Atheling jnr: the articles were reprinted in two collections, 'The Issue at Hand', (1964) and 'More Issues at Hand' (1970).
He was a fan of the works of James Branch Cabell, and for a time edited Kalki, the journal of the Cabell Society.