Kurzweil's The Law of Accelerating Returns{{anchor|The Law of Accelerating Returns|Law of Accelerating Returns}}
In his 1999 book
The Age of Spiritual Machines,
Ray Kurzweil proposed
The Law of Accelerating Returns, according to which the rate of change in a wide variety of evolutionary systems (including but not limited to the growth of technologies) tends to increase exponentially. He gave further focus to this issue in a 2001 essay entitled "The Law of Accelerating Returns". In it, Kurzweil, after Moravec, argued for extending Moore's Law to describe
exponential growth of diverse forms of
technological progress. Whenever a technology approaches some kind of a barrier, according to Kurzweil, a new technology will be invented to allow us to cross that barrier. He cites numerous past examples of this to substantiate his assertions. He predicts that such
paradigm shifts have and will continue to become increasingly common, leading to "technological change so rapid and profound it represents a rupture in the fabric of human history". He believes
The Law of Accelerating Returns implies that a
technological singularity will occur before the end of the 21st century, around 2045. The essay begins:
The Law of Accelerating Returns has in many ways altered public perception of
Moore's law. It is a common (but mistaken) belief that Moore's law makes predictions regarding all forms of technology, when really it only concerns semiconductor circuits. Many
futurists still use the term "Moore's law" to describe ideas like those put forth by Moravec, Kurzweil and others. According to Kurzweil, since the beginning of
evolution, more complex life forms have been evolving exponentially faster, with shorter and shorter intervals between the emergence of radically new life forms, such as human beings, who have the capacity to engineer (i.e. intentionally design with efficiency) a new trait which replaces relatively blind evolutionary mechanisms of selection for efficiency. By extension, the rate of technical progress amongst humans has also been exponentially increasing, as we discover more effective ways to do things, we also discover more effective ways to learn, i.e.
language, numbers, written language,
philosophy,
scientific method, instruments of observation, tallying devices, mechanical calculators, computers, each of these major advances in our ability to account for information occur increasingly close together. Already within the past sixty years, life in the industrialized world has changed almost beyond recognition except for living memories from the first half of the 20th century. This pattern will culminate in unimaginable technological progress in the 21st century, leading to a singularity. Kurzweil elaborates on his views in his books
The Age of Spiritual Machines and
The Singularity Is Near. ==Limits of accelerating change==