Wednesday, May 13, 2020

Reflections on Death, Immortality, and the Meaning of Life

We often hear it said that death plays a central role in providing our lives with meaning. The idea here is that immortality is either a curse of some kind or that a life without death is a life where we have no sense of urgency to complete our personal projects. But quite apart from the fact that there is rarely anything by way of solid argument given in support of this assertion, it leads to some quite unusual consequences. I have thought about a couple of these recently, and I would like to explore this in the following reflections.

To begin, let us imagine that we have what appears to be a perfectly normal human, let's call him Todd. Todd was born and grew up into adulthood under fairly unremarkable circumstances. But there is one remarkable fact about Todd: he appears to have an indefinite lifespan. More particularly, he remains in a continuous state of early adulthood for centuries or perhaps millennia on end. But current medical science can seem to find no explanation for why he seems to possess eternal youth. Indeed, for all we know, Todd may well be immortal.

On the other hand, it may very well be that Todd will indeed die of 'old age' at some indeterminate point in the future, for he could just be undergoing the exact same aging process, just at a much slower rate than the average human. So, with all the best evidence we have at our disposal, it is indeterminate whether Todd is really immortal.

Now with all that being said, we must ask ourselves: does Todd's life have meaning? Perhaps it is not fair to pose the question in such a broad manner, so let us be more specific. For any age T, where T is an age far greater than the currently longest-lived humans, does Todd's life have meaning at T? Suppose T is 200 years old. Is Todd's life meaningful at T? Maybe the great majority of us would be willing to concede that it is.

So let us now increase T to something like 500 years old. Is Todd's life still meaningful? If the answer is still 'Yes', then let us increase T yet again. If we keep following this procedure, one of either two outcomes will take place: Either we will change our answer to 'No' at some sufficiently high T, or we will always answer 'Yes', no matter how high T is.

Let us consider the first possibility. If we do switch our minds at some sufficiently high T, then we would be suggesting that T is the limit age for a meaningful life. So if Todd is closely approaching T, then he will soon be faced with living an indefinitely long life of complete and utter meaninglessness. What should he do when faced with this information? Should he perhaps take the drastic measure of committing suicide just when T arrives, thereby assuring that he has lived a meaningful life? But how can it be required of someone to commit suicide to ensure that they have lived a meaningful life?

If he doesn't go down this road, then should he just fall into despair and resign himself to a life of meaninglessness, even if there will surely be an endless variety of potential endeavors to which he could apply himself? But the most important question of all here is: how exactly can we non-arbitrarily determine the limit age for a meaningful life?

But let us suppose that we don't go down this road, and that we will always answer 'Yes' when asked if Todd's life is meaningful at any arbitrarily high T. If this is the path we take, then we have literally said nothing else than that an indefinitely long life can be meaningful, and thus we have rejected the notion that death is necessary for a meaningful life. So those who defend the idea that death is needed for a life to be meaningful seem to be stuck between a rock and a hard place.

We might also add that if an indefinitely long life is a meaningless life, then it follows that AI programs cannot have meaningful lives (if we use the term 'life' in this context to mean something like 'existence' or 'conscious experience', since AI programs clearly don't have biological lives). Since AI programs can be implemented on a variety of physical devices and since copies of them can be easily produced, they quite literally have indefinitely long lives. Should we then say that their lives are doomed to be meaningless? But surely AI programs, especially as physically implemented in robots, can engage in a multitude of meaningful endeavors. The simple fact that such meaningful endeavors do not have a foreseeable end doesn't seem at first glance to automatically write off the possibility that their lives can be meaningful.

Somewhat related to this point, if mind uploading becomes a viable possibility in the near future, then human minds will be in the exact same situation as AI programs. For once we have the ability to upload our minds onto computers and to make backup copies of them, then our lives will then be indefinitely long. Should we then say that our lives can only remain meaningful if our minds are encoded on biological brains? But why should biology be so closely connected to a meaningful life?

So to conclude, I don't view the notion that death is necessary for a meaningful life as being self-evident. In essence, what I would like to see in defense of this notion is at least something by way of decent argument. But quite apart from that, I would like to see more discussion on possible ways to live an indefinitely long, yet meaningful life. 

Friday, May 1, 2020

Notes on the Synthetic A Priori

I would like to explore some thoughts on the synthetic a priori that I have been having as of late. But before we dive into this, let us first make sure that we understand exactly what synthetic a priori propositions are supposed to be. This is important not only for the purposes of this article, but also because they play such an important role in metaphysics more generally.

The idea comes from the work of Immanuel Kant. To wit, he made two distinctions between a priori vs. a posteriori knowledge, on the one hand, and analytic vs. synthetic judgments, on the other. Simply put, a priori knowledge is any knowledge derived independently of experience. Prime examples of this kind of knowledge would be mathematics and logic. A posteriori knowledge is that which is gained through experience. Obvious examples of this come from the natural sciences.

Analytic judgments are propositions in which the predicate is conceptually contained in the subject. One example of this would be "All 3-dimensional bodies occupy space". If we understand the terms used, then we can see at once that the predicate "occupies space" is part of the meaning of the term "3-dimensional body". It follows at once that in an analytic judgment the predicate does not add any new information. Synthetic judgments are propositions in which the predicate is not conceptually contained in the subject. An example of this would be "All tigers are located on earth." We can see that in a synthetic judgment the predicate does indeed add new information.

Having this in mind, the question of how these two dichotomies are related naturally suggests itself. It seems clear that there are analytic judgments that are known a priori, purely conceptual propositions about the meanings of terms provide an obvious example. Too, it is also equally apparent that there are synthetic judgments that are known a posteriori, with the empirical propositions of the natural sciences being examples of these. But can there be synthetic judgments that are known a priori? That is to say, can there be judgments in which the predicate adds new information, but which can be known independently of experience? As Kant first adumbrated, this question is really the question concerning the possibility of metaphysics in general, since metaphysics proposes to be a purely a priori discipline that provides us with new information about about ultimate reality. (Of course, by 'metaphysics' here I mean metaphysics as first philosophy, and not the new naturalistic metaphysics that is now in vogue).

Now I am not interested for the moment in answering this particular question, so I will just take it as a given that there can be such propositions. What I am interested in exploring is, given that we do have such propositions, what are the various possible grounds for coming to acquire them? In what follows I will attempt to categorize the different possible ways of obtaining this knowledge.

To begin we should note that empirical investigation does not provide a sufficient ground for synthetic a priori propositions, for empirical investigation can only ever provide us with a posteriori knowledge. So too, the characterization postulate does not work either, for this only ever provides us with analytic a priori judgments about the nature of objects. But one obvious way is that which Kant himself provided; namely the transcendental intuitions of sensibility and the categories of understanding. In this way, synthetic a priori judgments are grounded in the very structure of the human mind.

I think another possible ground is the cartesian doctrine of clear and distinct ideas. To wit, we can gain access to synthetic a priori truths through an intuitive grasp of their content; the idea being that we can tell immediately, using nondiscursive methods, that certain synthetic propositions are apodeictic, thus delineating them as synthetic a priori truths. We can appeal to the example of intuitionism in ethics here.

Perhaps another way is the doctrine of mimesis, familiar from Plato's work. Under this doctrine, we first gain knowledge of synthetic a priori truths prior to our births by means of some form of sensuous experience. After our births we retain some faint memory of these experiences, and these can be uncovered through various means (whether that be mystical, rational, or otherwise).

Finally, there is divine revelation. Under this model, a deity or group of deities uses some means or other to directly inform us of synthetic a priori truths, and the very quality of such revelations provides epistemological assurance of their truth. Such revelations can come in a variety of forms, with scriptural inclusion and theophany being obvious examples. The divine revelation approach is also of interest because it provides some very intriguing connections between philosophy and theology.

That's all I have for this post. I just find this a perennially interesting topic, and I wanted to be sure to record my current thinking on the matter. Please be sure to let me know if I have missed out on any other possible methods.

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