So as not to mislead anyone, let me state right at the beginning that as far as I can recall there is only one 'Sci Fi' novel that has a vegetarian as its central character and that is Ursula Le Guin's award-winning 'The Dispossessed'. Shevek is a vegetarian because the planet his people have colonised supports no animal life on land so, of necessity, they have to learn to make the most of plants. This is a mere descriptive detail, not essential to the plot, but as you read on you realise the theme of the story is about responsibilities and choices that are highly relevant to everyone concerned with the environment, peace and compassion.
Personally, I find these books provide me with stimulating new ideas and entertaining stories at the same time. Of course, this is intellectual spoon-feeding, but ours is such a busy world, we don't have time to pore over great volumes of philosophy. I think it is no bad thing that books intended clearly for leisure reading should also give us some food for thought, albeit in an easily digested form.
Much of science fiction is set in the future or on far distant worlds but that doesn't mean it is bereft of any message for those of us alive today. If nothing else, it underlines the fact that we don't know very much about the universe, that human beings are just a very small part of it, and that often we don't really know what we are doing. Some novels very plainly say: 'If we carry on behaving as we are doing - this could be the future we are building for ourselves. It is up to us to choose.'
Anne McCaffery in her 'Decision at Doona' paints a grim view of an overcrowded Earth. There are no animals except in zoos. Horses and cattle have become rare, protected species. There isn't even any grass except the 'Regional Square Miles' which people are allowed to visit as a reward for some high achievement in their education or career. As an experiment, some people from these conditions are sent out to set up a pilot colony on a beautiful planet with an ecology similar to Earth's in the old days, but minus a dominant, sentient species. These people soon discover that grass, animals, rain, freedom to move, are important enough to be worth fighting for.
Another book by Ursula Le Guin called 'The Word for World is Forest' arose out of the concern she felt for what her countrymen were doing to Vietnam - to the environment as well as the population. Once again, in this story humans find a beautiful, untouched planet, one that is almost completely forest. But they don't see trees, only timber and the means of making a vast profit. They start to strip the planet systematically, heedless of the fact that they are having a devastating effect on the ecological balance. I won't spoil the story for you, but the native sentient beings, though previously totally unwarlike, do manage to find a way of fighting back!
Stories about life in a closed system like a ship on a long space flight where it may take whole lifetimes to complete a journey, or a barren planet where colonists live under plastic bubbles, show us a model of the Earth in miniature. It is far too easy to forget our planet is a closed system with only a limited supply of resources. These tales may help us to get used to the idea that one day recycling will be an absolute necessity, and we may all be living on TVP derived from plankton 'farmed' in the sea.
Stories which deal with encounters with other life-forms remind us of the thrilling diversity of Nature, and of the fact that intelligence may not always travel in the same shape as Homo sapiens. Up to now, we have been apt to think that there is no-one between us and the angels (if we believe in angels at all), but that may not necessarily be the truth. There may be beings at many different levels of intelligence and ability higher than ours, just as we regard animals as being ranged on various evolutionary steps below us. Science fiction warns us against being too complacent. We hope that when these superior beings discover the earth that they will have evolved beyond war and wanton cruelty, and that they will recognise that we are also intelligent creatures, their 'younger brothers' as it were, and treat us accordingly. I wonder if they will be influenced by the way we appear to treat our 'younger brothers' in the animal world when assessing our level of intelligence?
I have recently read Paul Anderson's book 'The Winter of the World'. Set many thousands of years into the future, in the middle of the next Ice Age, it postulates that our civilisation was wiped out when the ice first descended, leaving only small groups of survivors. At first they were isolated from each other but they gradually began to rebuild their cultures, though on a more primitive level. Trading routes were established, new empires were built, wars were fought as lost technological skills were relearned. At the time the story begins, there are efficient sailing ships on the seas once again and one nation has just about discovered how to send wireless messages in Morse code.
Generally, it looks as though the history of human civilisation is all set to repeat itself. However, one group of humans have been isolated long enough to evolve into a new species that can't interbreed with the others. No, they haven't sprouted horns or developed extrasensory powers. It is their instinctive behaviour patterns that have been changed. These new people - the Rogaviki - are certainly not vegetarians. They live by hunting the enormous herds of grazing beasts that roam the plains in the northernmost habitable zone. Yet in spite of their taste for flesh, one is left with the feeling that the earth and all the animals would stand a better chance if the Rogaviki ousted the older type of human. Instinctively, they hunted only for food, never for pleasure. They kept their population levels so low they would never deplete the herds, and they were born with a deep love of the land and the animals living there. Completely unaggressive among themselves, they behaved like all animals with strongly developed territorial instincts, attacking trespassers ruthlessly but never pursuing them beyond their borders. The moment the transgressor had ceased to pose a threat, the Rogaviki immediately resumed friendly relations. They carried no grudges, had no thoughts of revenge. Above all, they knew instinctively how to live without disturbing the ecological balance of their world. Is this a warning that if we don't learn our lessons soon, and accept our responsibilities voluntarily, Nature will force us to shoulder them, in a way we could never give up?
Space permits me to give only the briefest outline of a few books, but I hope I have given you an inkling of what I mean by my title. These novels can all be enjoyed simply as good stories. None of them sound as though they have been written with an 'ulterior motive' by an author with an axe to grind. I think the truth is that they have been written by thoughtful, sensitive people who have absorbed some of the vital issues of our times. The ideas put forward by vegetarians and the animal rights movement are radical, and need a certain climate of opinion before they can take hold, so although science fiction may not yet be the literature of our movement, I think it is doing a great deal to pave the way for us by bringing such issues as concern for the environment, and respect for living beings that are not quite the same as us, to the attention of a public that might not otherwise meet them.