I plan to write couple of futuristic articles, so decided to start with basic premise that has been guiding my thought process.
– We are in the midst of exponential growth. In fact we have always been, since the time we evolved to be called humans. The reason the exponential growth was not noticed in the past is because as with any exponential curve, the rise can be difficult to see in the initial parts, especially if the starting point is low and we started at a level very close to 0. Only now the rise in the curve is becoming noticeable.
– Significant advances are happening and will continue to happen in many different areas of science and technology (computers, networks, biotech, nanotech, 3d printing and so on).
– Although we know growth will happen, no one can predict, even within reasonable certainty, specifics of the changes. If you see predictions of the past, even the ones by authorities in their fields, you will find that most of them were wrong. Since rate of growth is higher now, predicting is all the more difficult.
– If we continue to make progress, even with reasonable bumps, there will be inconceivable changes in coming decades and centuries. The rate of progress is exponential (not linear). The changes will be of level which a common man today will refuse to believe and will find fictional. The possibility that within one century our life spans become significantly higher, with all body parts being replaceable, retaining youth till very long time – is very possible and would be called “just a start” in the context of this article.
– This exponential growth will not last forever. Like most exponential curves, growth will flatten out at some point. But we are far from that level. The growth has just begun. Some specific technologies may and will find a dead end along the way. But with millions of year behind us and many more than that in future, assuming we will reach saturation in mere couple of hundred or thousand years from now, is not reasonable.
– There is a chance that we continue to make progress for couple of centuries or more with only minor bumps, with derailments lasting a decade or couple of decades (example – major market crash or terrorist attack). In fact such bumps would be considered very reasonable and if we experience nothing bigger, it will be considered almost a best case scenario.
– There is also a chance that our civilization gets destroyed and we get pushed back by centuries or get totally destroyed. We could be victim of our own progress (example terrorists use biotech to destroy whole civilization) or a natural calamity like big meteorite hitting earth or something hitting Sun (very unlikely though) and so on. One can write long article of this topic itself. Some scientists believe that lot of advanced civilizations (much more advanced than ours) have existed in space and most of them would have reached extinction at some point rather than continuing to survive. Michio Kaku’s book ‘Visions’ covers this area very well.
– In nutshell, starting from now, if we can achieve a century or couple of centuries worth of progress, we would be at a level of advancement which is unthinkable. However, due to derailing factors mentioned above, in place of “couple of centuries”, the actual time when we get there may be much longer, even millions of years or may never happen.