The division between the subjective and the objective defines life.
Our experience is subjective because we observe it. Through experience, we learn about a world which is independent of the subjective world, in which objects persist independently of our observation of them: the objective world. This distinction is incredibly significant; it is certainly one of the first distinctions we learn. This book follows an inverted development in this respect: it begins with the physical universe, and then proceeds to examine the subjective universe.
It is not possible to resolve which of the subjective or physical universes ultimately contains the other. Saying that the subjective domain is a part of the physical universe, and that the physical universe is more than the combination of all of the subjective universes, implies that the objective domain exists independently of our perception of it. This characterization of things amounts to the claim that “if a tree were to fall in the woods and no one were there to hear it, it would still make a sound” . Although this point of view is widely accepted, it is not necessarily true: the strongest claim that any of us can make on the basis of our experience is that a tree falling makes a sound if we hear it (or otherwise measure it).[50]
An apple has properties that we cannot directly perceive, such as chemical bonds, electromagnetic forces, etc. Among the properties of the apple that we can perceive, such as the exterior of the apple, we only see aspects of the side that faces us. The distinction between what we can and cannot observe, is the distinction between the subjective and the objective domains. The subjective universe is a high-dimensional thing that consists of all the things that we perceive in our lifetime, and encompasses inner phenomena such as thought. Although we are often not aware of all of our neuronal processing, it is still a part of the subjective domain (although we may not always pay attention to it).
Although it is misleading to define a sharply demarcated line between the subjective and objective domains, we will (somewhat arbitrarily) make the claim that the border between the subjective and the objective domains is the border of the nervous system (which is taken to include both the central and the peripheral nervous systems). Note that this border is established from the objective point of view: from the subjective point of view, there are no borders (i.e. it is not possible for an individual to perceive the edge of their nervous system).
The objective domain consists of those things which are not referential.
By social convention and experience, we establish that there are things which are not directly perceived, but that are still present. These things are collectively known as the objective domain. The hair on the back of our head, assuming that we do not perceive or otherwise sense it, is a part of the objective domain (i.e. something is not subjective only in virtue of being a part of our body). Again, a thing is a part of the subjective domain in virtue of the fact that we perceive it. Hence, the hair on the back of someone else's head may be a part of our subjective domain.
This fact illustrates that the subjective/objective dichotomy is different than the dichotomy between self/other. The self is an organism whose boundary is determined from the outside, but the subjective universe is determined by the perception of that organism (i.e. from the inside). Again, note that the subjective universe does not exhibit a boundary when viewed from the inside; by merely looking at two hands, one of which is mine and one which is yours, there is no necessary reason to assign the label mine to one of them (based on immediate perceptual evidence, and neglecting sight of the arm that connects to a body). Of course, I have physical sensation of my hand that I do not have of yours, but I do not have physical sensation of my hair, and that is still typically considered a part of my self.
One of the primary distinguishing characteristics of living things, which are the containers of subjective universes, is the ability to move about. Our ability to move our body is important for both the formation of one's self-concept as well as the determination of other objects as animals. Therefore, the next section briefly examines several externally observable differences between the living and the lifeless.
The actions of lifeless things are determined from the outside.
An object is affected by gravity in virtue of its mass. Expressed slightly differently, there is a property called mass in virtue of which one can determine the action of the object. A rock is going to fall to the earth with a certain inertia in virtue of its mass. In this case, the rock's mechanism of action is so obvious (or transparent) that we might even say that the rock has nothing to do with it. This mechanism is in stark contrast to the mechanism behind the action of animals, which often have extensive brains and complicated (or at least opaque) mechanisms of action. A snake slithers toward food in virtue of various muscular and neural machinery. Owing to this machinery, the motion of a snake takes into account the world as that world has been experienced over the snake's lifetime (as opposed to the motion of a rock, whose wellsprings of action are a good deal more immediate).
The extent to which the immediate external causes of a thing determine its mechanism of action is the extent to which that thing is not self-determined. Self-determination often entails having the intrinsic properties of unpredictability and intelligence (the latter is necessary to rule out pure randomness). Because animals have some internal complexity or memory in virtue of which they act, animals are free (as opposed to being controlled directly by external forces). The cause of the action of an animal or otherwise independent entity comes largely from within, even if that within has ultimately come from without.
As an example of causation, if the wind rustles in an apple tree, and a branch shakes, and an apple falls on my head, one might say that the wind caused the apple to fall. Not only did one thing happen before the other, but the earlier thing made the latter thing happen. As a result, the later thing was unavoidable; the cause required the effect to occur. In this understanding, the future is uniquely determined by the present; it is simply waiting to unfold. Before the effect (the apple falling), the cause (the wind blowing) is present; that cause, in turn, can be seen as the effect of yet another cause (perhaps the low pressure system in the area).[51]
There are several things to consider about the mental model behind this causal description of the falling apple. The rustling wind, at an earlier time, consisted of bits of matter and energy which were dispersed throughout the world: when all the causes and conditions come together in the right way, the tree is shaken, and the apple falls. One implication of this description is the billiard-ball model of causation. Despite the fact that the wind is dispersed, the billiard-ball model implies that one thing causes another thing, which causes yet another thing. This view of things is rigid in that it presupposes a unique decomposition of space into objects, and then implies that one event is the unique (or at least the primary) cause of the next event in the causal chain. However, there is no unique decomposition of reality into things, and even if there were, many (if not all) of those things contribute to any given effect. The apple would not have fallen unless the stem was weak, and gravity was present, and any number of other causal factors all came together to contribute to the result.
If we accept that animals are determined, we may describe their behavior with a deterministic language: they do certain things because from one point of view, those things were inescapable. In this case, however, we must also accept that they exist in a multi-faceted causal context, where part of their determination is internal and part is external. This means that we can still use the language of volition: in fact, it means that the language of volition is applicable to a larger class of objects, just as is the language of determination. In essence, if free means caused from within and determined means caused from without, then the boundary between freedom and determination becomes merely a spatial boundary. Applying the language of volition to inanimate objects, we might say that a rock decides its future course of action in virtue of its mass. A radioactive rock will cause clicking on a Geiger counter in virtue of its radioactivity. Of course, the rock always makes the same decisions: it is not all of a sudden bestowed with lots of creativity. It does not engage in a thinking process: that is in part what makes it a rock, instead of a person. Subjectively, though, this kind of talk can transfer a feeling-tone to inanimate objects which was previously reserved for animate objects. It can also help us to feel mercy for people who make stupid decisions. Of course, all of this is an uncommon use of language: we are stretching the boundaries of what we generally mean by a free decision. But to some extent, that is exactly what the debate of free will and determinism is all about.[52]
The subjective domain consists of those things which, for some individual, refer to things in the physical universe.
As discussed in the previous section, which objects are alive can be partly assessed based on the internality of their causes. However, it feels odd from a subjective point of view to say that we are caused: we prefer to say that we are free to do as we like. This section looks a bit more closely at causation from a subjective point of view, or individual volition, in light of the fact that physics seems deterministic.
Living things are described as having a choice.
Many people believe that their fate is escapable: hence, they apply the language of causation to inanimate objects. As for themselves, they are free to do whatever they decide to do. In fact, determinism admits that people are free to do whatever they decide to do. Further, people are free to decide what they decide to do. In light of this, even determinism is quite free. What determinism disallows, however, is that people that came into being can recursively choose what they decide, in a way that begs an infinite regress. According to Schopenhauer, “A man can surely do what he wills to do, but he cannot determine what he wills” .
If living beings are completely free in the sense that they can determine both their current choices and all the causes that led to that determination, then the implied infinite causal regress necessitates that these beings have always existed. In other words, if they are their own cause, then they must already have existed in order to determine their subsequent choice (assuming that they did not come into existence causelessly), and in this process it seems that there could be no first moment (as they would not have been around in the prior moment in order to cause themselves). On the other hand, if individuals are born from causes and conditions other than themselves, then they are determined (at least originally) by that which is other than themselves.
It is probably not a coincidence that people who maintain the existence of ultimate individual freedom often hold that a soul entered the body from somewhere else, and that this soul has existed forever. Pre-existing selves, which have existed forever, allows ultimate freedom to be maintained even though bodies are created in the context of a deterministic world.
Many people have gone to great lengths to deny causality: some individuals try to avoid this argument by saying that freedom is a form of randomness. Whether or not it is possible to be truly random, it is quite possible to have numerous causes instead of just a few, which would lead to complex (if not truly random) behavior. However, true randomness as a source of action is probably not enormously satisfying, because even though we are no longer determined , our freedom to do things becomes entirely random: although we win freedom from determination, we simultaneously strip volition of any meaningful intent.
There is exactly one thing for which ultimate freedom is not a paradoxical notion: everything. Everything is entirely free, and is in no way unfree: it could not possibly be controlled or determined by something else, since there is no other thing whatsoever. Hence, just as the notion of everything depends on one's perspective, whether something is free or not depends on perspective. From an objective perspective, it may be impossible for a part to be free, since that part exists in a causal context. That part, however, may be an entire subjective perspective, and from that point of view it is a whole and could not possibly be determined by anything else. These two truths do not contradict one another: they are each valid from their own point of view. Considered as a part, a thing is determined by other parts: as a whole, a thing has nothing else by which it could be determined.
[50] If you are someone who believes that there is no objective domain above and beyond the many subjective domains which we describe as being a part of it, feel free substitute the term “multi-subjective universe” for the term “physical universe” , and assume that talk about the physical universe is talk about it as it is observed (or could be observed).
[51] This logic entails both that causes require effects and that effects require causes.
[52] Treating what was previously considered to be mental as material does not remove the mental aspect of things. In fact, if the language of volition applies to us, and we are material beings, then it makes sense to apply the language of mentality to other material things. This approximates a doctrine known as animism or panpsychism, which holds that all things have a psyche, or that all objects have a (limited) subjective experience as well as an objective one.