Challenges and Promises

Some of the challenges and promises that would stem from the creation of digital minds are presented and discussed. In particular, this chapter addresses the possibility that, in the future, there may exist digital persons, digital minds that have personhood rights and duties. The non-obvious possibilities raised by the creation of digital minds are discussed in some detail, including the possibility of time-travel, eternal life, and unlimited duplication. Many of the questions raised by the existence of digital minds have no obvious solution in our current legal framework, and will need to be addressed in the coming decades. Digital minds may decide to live entirely in virtual reality, using technologies that are now under development. That would raise possibilities that are hard to phantom, given our present day knowledge.

The Universal Machine

This chapter covers the development of computing, from its origins, with the analytical engine, to modern computer science. Babbage and Ada Lovelace’s contributions to the science of computing led, in time, to the idea of universal computers, proposed by Alan Turing. These universal computers, proposed by Turing, are conceptual devices that can compute anything that can possibly be computed. The basic concepts created by Turing and Church were further developed to create the edifice of modern computer science and, in particular, the concepts of algorithms, computability, and complexity, covered in this chapter. The chapter ends describing the Church-Turing thesis, which states that anything that can be computed can be computed by a Turing machine.

The Exponential Nature of Technology

This chapter provides a brief review of the history of technology, covering pre-historical technologies, the agricultural revolution, the first two industrial revolutions, and the third industrial revolution, based on information technology. Evidence is provided that technological development tends to follow an exponential curve, leading to technologies that typically were unpredictable just a few years before. An analysis of a number of exponential trends and behaviors is provided, in order to acquaint the reader with the sometimes surprising properties of exponential growth. In general, exponential functions tend to grow slower than expected in the short term, and faster than expected in the long term. It is this property that make technology evolution very hard to predict.

Speculations

This chapter, the last chapter in the book, presents some far-fetched ideas about the future of technology and the human species. It starts by discussing the concept of technological singularity, an even that would create a discontinuity in the evolution of technology. The idea that mind uploading may one day become possible leads many people to believe that the singularity will one day happen, making it possible to eradicate death entirely. Approaches such as cryonics, that aim at preserving bodies until the singularity arrives, are considered and discussed. The creation of digital minds also raises complex questions about the possible future existence of intelligences much superior to those of humans, leading to the problem of how to deal with such intelligences. Finally, the chapter analyses the possible relations between digital minds, the long term future of technology and how these questions may be related with Fermi’s paradox: if there are many intelligences in the galaxy, how come we never met any?

Brains, Minds, and Machines

This chapter presents an analysis of the different approaches that may lead to the creation of artificially intelligent and conscious systems, which I call digital minds. In particular, it considers three different avenues that may eventually lead to intelligent systems: synthetic intelligences, neuromorphic intelligent systems, and whole brain emulation, also known as mind uploading. The challenges and potential of each of these approaches are described and analysed. Existing programs that may be the prototypes of future intelligent and even fully conscious systems are presented and examined. The chapter concludes by presenting a brief overview of the complex questions that surround the concept of consciousness, and some of the experiments that have been performed in order to advance our understanding of this phenomenon.

Understanding the Brain

This chapter summarily describes some of the technologies that are currently being used to image living brains and understand brain behaviour. The important projects in this area are briefly enumerated, as are the many technologies used for brain imaging. The computer models that are used to integrate the obtained data, brain networks, are also briefly described, together with the methodologies used to analyze them. Also covered in this chapter are some of the techniques used to dissect and image live brains in order to obtain detailed information about the fine structure of brain tissue, such as electron microscopy. The chapter finishes by surveying the techniques used to simulate sections of brain tissue, and uses these simulations to compare the computational efficiency of biological brains with the computational efficiency of brain simulations in modern day computers.

Cells, Bodies, and Brains

This chapter describes evolution as a long-running algorithm that has designed all species on Earth. Evolution, a process discovered by Charles Darwin, has been working for more than four billion years to obtain, at first, simple unicellular organisms (prokaryotes) and, later, much more complex life forms, based on eukaryotic cells. Evolution worked not with bits stored in a computer memory, but with replicators that are digital sequences written in very long DNA molecules, the genomes. Complex cells, which are the results of this optimization algorithm, eventually organized themselves in vast multi-cellular complexes, leading to the multicellular organisms in existence today and, ultimately, to humans and the human brain, the most complex information processing device we know.

The Red Queen’s Race

This chapter introduces the idea that technology, invented millennia ago, is developing at an even increasing pace, creating the need for all systems to develop to avoid becoming obsolete. This is called the Red Queen effect. The current generation has seen the appearance and rapid development of many new technologies, from digital computers and cellular phones, to DNA sequencing and genetic engineering. However, the next decades will witness an even faster technological development, leading to the appearance of economic and social realities that we cannot even dream of. Computer technology and biotechnology will come together to create changes in society that will make the last decades look like slow-paced, in what respects technology development.

The Quest for Intelligent Machines

This chapter addresses the question of whether a computer can become intelligent and how to test for that possibility. It introduces the idea of the Turing test, a test developed to determine, in an unbiased way, whether a program running in a computer is, or is not, intelligent. The development of artificial intelligence led, in time, to many applications of computers that are not possible using “non-intelligent” programs. One important area in artificial intelligence is machine learning, the technology that makes possible that computers learn, from existing data, in ways similar to the ways humans learn. A number of approach to perform machine learning is addressed in this chapter, including neural networks, decision trees and Bayesian learning. The chapter concludes by arguing that the brain is, in reality, a very sophisticated statistical machine aimed at improving the chances of survival of its owner.

How the Brain Works

This chapter provides a brief introduction to the way the brain works. It starts by describing the physical mechanisms used by neurons to send and receive electrical signals, and some of the experiments that led to the understanding of these mechanisms. It then describes how neurons are organized in networks and uses some particular structures in the brain, namely the brain visual cortex, to illustrate the signal processing that takes place in the brain. The chapter also covers, very briefly, the few known mechanisms that are used by brains to self-organize and create the structures that are present in fully developed brains. Mechanisms that lead to brain plasticity and the creation of memories are also examined, with a special emphasis of the synapse reinforcement process that is known as Hebb’s rule.