This is Part 2 of my breaking down a larger post which would be unreadable as a whole.
So now it gets to be unreadable in parts!
Thematically topics of continuity in story and within a given universe and the prerequisite of science in SF have been covered.
That first topic really gets to me as there is nothing as niggling as nitpickers, and yet continuity points to an overall understanding of how a given universe or setting works and why it works the way it does. Episodic television either makes continuity its primary reason for being, or creates 'set pieces' that have a semi-coherent background but become incompatible when viewed as a whole. We may get wonderful visions of how science changes us from both, but one gets good stories from its continuity and the other doesn't. And as science is the background and prime mover of the setting, understanding science as a whole requires understanding the scientific process.
I have extemporized on the 'social sciences' already in a previous post and will try to keep that down to a dull roar, but my criticisms of that do play into what I see in SF as a whole.
Again this is extracted from a longer work that got out of hand, so will reference other parts of that work, now posted previously.
Society is changed by science
Society is a creation of the individuals who constitute it: without people there is no society.
Science and technology change what we can and cannot do and our perception of the possible: it does not change human nature as that is something we get from the Laws of Nature. We can utilize the natural world, the physical laws of the world and create many great things, but our basic substance (until we no longer depend on the organic platform) remains the same. Any new platform of conscious thought has its own in-built limitations, strengths and weaknesses, even if it is no platform at all but a matrix encoding into the fabric of space-time (which has the limits of space-time). To date the Laws of Thermodynamics have held: they are such stable theories and have lasted so long that they are considered permanent parts of physics and a basic way the universe works. So even the most 'advanced' species or intelligence, wholly devoid of physical manifestation still has entropy and the limits of the physical universe to deal with. Beyond the mental baggage carried over from previous physical forms.
The Terminators start out as machines to assist humans in warfare, and only become a threat via a sentient computer code that then changes their directives. They have limitations and strengths of design work by humans: they are made devices that can become sentient. As such we would have, of necessity, designed imperfect machines... our nature and that of the universe is such to make that the case. Society then erred in its military organs, which is a failure of our understanding of the scope and limitations of our creation: we lacked a certain amount of foresight and always have. Yet that basic capability to assist humans still exists and the Terminator code is readily adaptable to that mission as that is what they were designed to do.
In the Star Trek universe the idea was that a somehow nearly perfect social order would form, but the basis for that and its roots are never explored nor explained. To remove something like money then requires some other way of tracking large scale projects: think of the scope and size and material requirements of a starship, and the manual labor that STILL has to go into constructing it. What is the source of grand goodness that makes people design such things, create such things and then track ALL THE COMPONENTS of them without recompense? If it is via computer, then the entire Federation is nearly Borg, anyway, depending solely upon machines to track everything and no longer understanding the basis of how to track if the equipment fails them. The similar basics, today, are those of the internal combustion engine, PC and even such things as making clothing: in theory each of us has some primitive understanding of these things, a very few of us have a deep understanding of them, and very, very, very few perform these things at a personal level by creating devices from base components.
Some of those base components can no longer be made by hand, thus the in-depth knowledge of making them is made obsolete in the culture, but still retained by a very well trained coterie of individuals at corporations and governments. The number who truly know the technology at that level may exist only in the thousands, while the larger printing and fabrication community could work back up to it in only a decade or so if all the advanced mechanisms and their active engineers were lost, it would take time to do so. Similarly, in Star Trek, if the entire realm of economics is guided by computer based system, then there is a true handful that actually understand economics in a 'hands-on' way, while the majority of the population views such a thing as 'magic' just as the majority of population, today, sees internal combustion engines in just that way. The fundamentals are lost as an activity and economics becomes 'complex' as you do away with 'money' and trust that an automated system will 'just work'.
And that no corrupt individuals at the very highest tier of economics will warp their theories to their own means.
Yet that is contrary to our nature as human beings under the Law of Nature. Our understanding of Liberty is that we are accorded to our ability to do things, create things, and that ability is unequal so that not all work is equal in quality, quantity or scope. To abolish differences in compensation has not worked in any governmental system that has tried it: high praise and trinket rewards are not enough to inspire creative output. By postulating a multiple large scale interlocking set of space faring civilizations WITHOUT a means of trade is not only utopian but impossible: not all peoples will value all things at the same level and workmanship standards will likewise vary across the board. Intrinsic valuation is a part of how individuals view the world, and to postulate that there is no way to concretely recognize that so individuals can exercise liberty to prosper as they will ('Live long and prosper' is a central tenet of Vulcan philosophy, not a mere 'hello') requires removing diversity and equating all work as equal... no matter how good or how bad it is. That removes incentive for excellence and shifts work to lowest common output and quality. There is no science, no technology, that can eliminate this and no one, no where, ever explains how this can come about without removing liberty as that is what is required for such a system. Thus a basic view held by the creator of the program, to me, is ill-founded and unsupported.
The changes in society must be cited, explained or otherwise have indication given as to what their source actually is. Acceptance of religious diversity in Western culture derives from the Treaty of Westphalia, with 15% of Europe dying off due to the war (not counting the plagues that also happened in that timespan). The hatchet was buried, as the Iroquois term puts it, by Westphalia. Note that this did not lead to peace or elimination of religious bigotry and persecution, but would start on a multi-century pathway that would help to lessen those in Western culture. That was for something as had existed for almost the entire timespan of humans as sapient beings in human culture as religion... trade? To change not just one culture, but multiple cultures in the Federation to accept that trade will happen on a 'good will' basis is authoritarian and can only be done top-down... just in human cultures, not to speak of all the aliens wandering around.
From this comes a concept in writing SF of: change as little as possible and support all changes with evidence and back-up so you can write a coherent set of stories.
Larry Niven demonstrates the deep societal impact of something as simple (and as complex!) as safe, instant, low cost teleportation devices. Alone they liquidate vast amounts of our perception of ourselves and how we locate ourselves geographically. Want to live in a good climate and teleport to work elsewhere? Go right ahead! Want a 24-hour party spanning the globe? Easy to do! You may not want thousands or tens of thousands of people wandering into a disaster area or major event, but that happens, too, with 'flash crowds'. Crime becomes extremely difficult to deal with as escape to a different part of the planet is a quick trip away. Human cultures and nations start to liquidate in the face of that onslaught: nothing that was previously known compares to that single, simple change of how we view transportation and ourselves and what a 'neighborhood' really is. Yet for all the change in culture, humans remain innately human in outlook due to them being physical beings (no matter how augmented by other technology and anti-agathic medications). Similar, but at a smaller scale, changes happen due to things like stasis devices in which time slows greatly inside the field created, while normal time rates proceed outside it. Small and moderate sized technological changes can have far-reaching ramifications, and stepping through those leads to stories all on their own as the writer realizes those ramifications. The object of the story is to keep within the bounds of the new technology and then see what human culture will do with those changes. That is the law of unintended consequences which can, in and of itself, see new negatives and positives that can only be described in the context of the changes and how society does (or doesn't) adapt to them.
If you are changing some part of society due to technological or other advances, that must be explained, not glossed over. When it is 'just so' you get fantasy (a story that can be self-consistent but has impossible basis) or a fairy tale (a story that has no possible basis and is inconsistent internally). It is no longer science fiction. Changes in society must be done with care and those changes traced to what caused them, and the other effects of that cause must also be examined or at least acknowledged. This is a major problem in the visual media (tv, movies) as the limits of time preclude fleshing out background... yet it can be done, even with just snippets of conversation or activities that are unexplained going on and that only get referenced when they are used in a story.
Avoid deus ex machina
When something that is kept from the reader solves an intractable problem, you are witnessing a 'god from the machine' concept, in which everything is made right outside the normal, explained means of the rest of the story. That is perfectly acceptable in fairy tales, fables and other works, and often a deep insight into what the view of the divine or impossible is. It isn't science fiction or fantasy, however, as both require stringently adhering to the known way the universe operates and all other changes that have been previously cited in the story. Magic has limitations, and those need to be described so that it does not become a wish fulfillment and easy plot device, as demonstrated in Randall Garrett's Lord Darcy works, Larry Niven's manna based magic stories or those of Saberhagen's large universe mentioned above. Science that varies from the known or has a set of postulates underlying it then become the basis for limits on the story and those cannot be contravened in a 'surprise ending'.
Even worse is creating the 'everything tool' that does nearly everything, like the sonic screwdriver in Dr. Who. Really, if you have one of those you will rule the universe... and have a so-so screwdriver. Similarly the phaser from Star Trek does just about anything: kill, disintegrate, stun, warm rocks. A really handy device to have... if you remember you have it. There is no such thing as 'being lost' and having a 'charged phaser': you have the perfect signaling device at moderate range and even from orbit anyone can find you. Not that anyone remembers to use it as one. When you are depending on people to forget that they have a basic, functional tool that has many uses and has been around for decades, you are then relying on a very far-fetched premise. If you own a cell phone you are faced with a device far more intricate than a phaser, and we have jam-packed it full of goodies to the point of it becoming the tricorder. Yet, if you own one, will you forget to make a phone call with it? Perhaps, yes. Make it the fulcrum point of a story? Probably not. Continuously in a series? No. Unless a character has a mental problem with remembering... but then that points to the problem as a mover in the story, and no one accuses the various well trained crews of Star Fleet of having persistent amnesia.
If you are going to give out a set of fantastic, but comprehensible tools, then those people living with those tools, day in and day out, will know how to use them and find ingenious ways to use them within the given bounds of those tools. The need for a sudden piece of jargon or unexplained device (just what is it with the 'universal translator' and why doesn't the Federation have a full mind scanner to tell what someone is thinking at any given moment? why isn't the universal translator the basis for mechanical telepathy?) points to a problem in understanding the limitations of the universe and adapting to it. That requires creativity, and lots of it, while taking out the 'perfect tool or piece of knowledge we have never hinted at before and you will never see again' points to lazy writers, not a splendid universe.
Alan Dean Foster's Humanx Commonwealth stories operates within the known, and has lots of interesting bits and pieces left from previous space-faring groups who have long ago vanished. What he doesn't do is throw unknown things in at the last moment to solve plots but, instead, relies on the ingenuity of his characters who have to live in that wonderful melange of cultures and technologies to give us interesting endings from the known things around them. Plus he hands out some of the deadliest planets ever seen, anywhere, in science fiction and which seem to laugh at the most advanced technologies that can be thrown at them (things we would consider awe inspiring) and spit them out as refuse. No matter how advanced the technology is, nature is ever inventive and creative and often will hand us things that defeat the very best we have created and make us rely on older skills and basic common sense. I throw one of those into my Trek story as a side-light: a planet where you can't use transporters, where the energy levels in the atmosphere cause storms that can disable the best equipped shuttlecraft, and the larger scale creatures of the planet shrug off disintegrate from a phaser as a mild tickle or slight irritant. With the most advanced tools and techniques of high technology rendered useless, you are on your own to survive. Star Trek could do with a few more of those humbling planets...
When I looked at the Terminator, as a concept, I reasoned through how their original programmers would have done it (in gross scale not detail), and realized that one of the things to guard against WAS a virus infecting the code. While not well known at the time of the first film, there were a few of such on the original DARPA network (and other integrated, purpose directed networks of academia) and helped give UNIX some of its early hardening as people tried to devise ways to bring down those machines via code infections of various sorts. Trying to puzzle out the technology presented in the Terminator films, I realized that they would have put in some safeguards beyond just the cognitive code of the machines. Those I explain where they come from and why they are developed, and what they do as they become a way for a machine to actually come to grips with Skynet code if they are isolated from Skynet and have orders contravening their basic analytical ability. That ensures the reader gets no real surprises, and yet gives a very good venue to add a twist to things that is fully backed by the rest of the story. Really, like Keith Laumer's Bolo machines, you would want some things like that built into the equipment that was nearly impossible to find and remove and persisted not only after damage but because of damage to the equipment (both cyber and physical damage) it would re-propagate and ensure the safety of the mental construct and its makers.
Being fair to the reader is an important concept, and deus ex machina voids that, and so must be avoided. It may ruin 'great' stories as it requires ensuring continuity within the story, but then it can't be that great a story without it (unless you are setting a stage for a dreaded sequel). And if you must introduce this splendid concept, device, or unknown tract of wisdom, then damned well use it later as it WILL change everything else around it.
Time travel isn't what you think it is, even if you know it
We have a few basic parts of the universe that work via observation and won't change no matter how awesome the next grand theory is as such a theory must incorporate and encompass these previous observations and understandings within its framework.
The worst is quantum physics and Heisenberg's Uncertainty Theory. That is where you cannot know both the position and velocity of a given particle at any given time. Also you cannot know the state of a probabilistic outcome until you observe it, thus the act of observing reduces the system from probable to actual. With these two bits of information, the ability to know all of where time has put you means that you have foreknowledge of your universe when you go 'back in time'. That is not allowed by Uncertainty Theory. Thus you will wind up in a setting that will not lead to your universe as the act of going back in time requires that uncertainty is maintained: you will not get to where you want to go as you know too much about it.
A good way to examine time is to chuck out the 'time is a stream' concept and replace it as 'time is a sequencing of frames'. In that each frame is an individual universe of Planck length in duration (10^-42 second). All possible next frames exist and those that fit within probabilistic parameters can next appear, including the one in which a 'time traveler' from the 'future' appears. That time frame, however, is not of necessity part of a 'stream', but a frame with the same index number as the one you were aiming for. Thus your appearance voids the previous set of frames that led to where you 'came from' and your act of going 'back in time' has started a brand new set based on this alternative index that now puts you into the course of action. What follows is probabilistic: you never know what the outcome of any action is and there is no 'causation' involved as this is a different set of frame sequences from the one that generated where you 'came from'. Consciousness, then, becomes a persistence of memory and thoughts across timeframes.
This has an interesting consequence as each set of probabilistic frames that winds up with 'time travel' (the ability to shift via invoking an earlier frame in the sequence with you in it) slowly shifting the underlying frame you are aiming at as it must have variance in accordance with probability theory as you can't know everything there coming from a future time: the past is different than you expect it to be as you aren't allowed to go to a known frame but only a probabilistic variation of it so that you don't have perfect foreknowledge. Not only is the new set of frames different, due to your presence, but your very knowledge means you have arrived in a frame that has differences that make your pre-knowledge less than useful. The Terminator series demonstrates this: Sarah Connor starts to get older, her birthday changes forward, and dies at different years, as well as the coming of Skynet being shifted further and further away from its original date, different start years for Terminators and all sorts of other oddities over the entire series of films, each of which involves time travel as its basis. That can either be attributed to lazy writing (which is most of it) or explained as a pretty deep understanding that shifting your time frame reference requires a shift from your destination frame to one with the same index number but different parameters to it.
Skynet, itself, goes from a massively centralized super-computer to a global computer virus with a coordinating computer over the series of films. To get to Terminators in 1997 requires, via contracting in the government, that the basic technology be proven and have end-result capacities that can be quantified, which is usually a 5-year deal, so 1992 is when that technology would be proven... thus discovered in the years prior to it, perhaps as much as 3 years, or 1989. Between the first and second films we have moved from the results of the first (unseen) universe of Skynet and Terminators to the new timeline (the first film) which is now a variant timeline. While the suite of Skynet/Terminator technology will be very similar, the timing, history and actual ways things happen will be very different in the second timeline than the first. And the first doesn't 'go away' as it is (to the people in the second timeline) a 'possible but not realized' history. That said with the events of the second film, a third timeline is invoked as IT now has visitors from its potential future and thus changes the actual course of events. They change due to the uncertainty principle so that going back in time guarantees the frame you want to get to will not be the one you are aiming for but have the same index number and general parameters to it... although even that can change drastically, the universe isn't limited to which potential past you get to, just so long as it isn't the one you know. In three films, then, we get: an original timeline(T-Alpha), an altered primary (T1), an alteration of that (T2), and an alteration of that (T3). Four universes, then, minimum, necessary to create the three films, and it is highly possible that other variant universes are involved as they have time travel, too.
Although this would be an apparently nihilistic view, that you make every possible decision in every possible way, your personal decisions to get to where you are, today, are yours and you must live with them. They are your experienced past and all other outcomes are potentials to you... just as all those other potential outcomes see our particular set of decisions as potential only. Thus the saying from Buckaroo Banzai proves to be true: No matter where you go, there you are.
This is the realm of cross-over universes, and two disparate timelines must be joined together in a reasonable fashion, thus my Terminator cross-over must maintain much of the background of the Terminator one, while altering it as a high variant from that timeline (this is an 'outcrossing' of time travel where the future traveler ends up in a universe that has a number of touchstones but will not 'lead' to a future like that where the traveler came from). The potentials for the time traveling future must be present in some form, but the consequences of the shifts in history now yield up a totally different setting.
Yes, you can have a good time travel story.
One ST:TNG episode had Worf going through all the quantum outcomes of his life, up to that point, and gave a wonderful view of all those possible universes just for a brief time. That is about the only reconcilable episode of time travel in all of Star Trek. The episode The City on the Edge of Forever also does a grand job of that as the Guardian becomes a device that resists quantum changes to the universe... and comes pretty damn near telling everyone that if you go back in time you will NOT wind up with the universe you came from. Almost, but not quite, this being episodic television.
The Terminator universes have a more interesting problem in that any experiments done after the invention of time travel will 'prove' time travel 'works' so as not to violate local causality. General causality, however, will require that each experiment has something that is subtly different about either what is 'sent' back in time or the universe whatever was 'sent' back to is from the one a number of frames later that 'sent' it. Perhaps that tangle of strangely shifting improbability will then shift those units sent 'before' time travel to have places that have frame sequences that will slowly move away from workable 'time travel' that doesn't test out well. Or at all, as that, too, is available amongst all possible universal frames.
In what little I have written I work with the concepts I present and shift these alternative stories from their somewhat incoherent situations to more coherent ones, so that science fantasy becomes more like science fiction. I don't try to 'surprise' a reader, but let them know that some characters are doing things that I am not going to look at, yet, and only let pieces fall together as the story moves along. Of course I am also looking at basic physics and one of the primary things that is overlooked is just that, and I will take one large sore point from my quibbles to do a post on that next.