Part of the sequence: Rationality and Philosophy

In my last post, I showed that the brain does not encode concepts in terms of necessary and sufficient conditions. So, any philosophical practice which assumes this — as much of 20th century conceptual analysis seems to do — is misguided.

Next, I want to show that human abstract thought is pervaded by metaphor, and that this has implications for how we think about the nature of philosophical questions and philosophical answers. As Lakoff & Johnson (1999) write:

If we are going to ask philosophical questions, we have to remember that we are human... The fact that abstract thought is mostly metaphorical means that answers to philosophical questions have always been, and always will be, mostly metaphorical. In itself, that is neither good nor bad. It is simply a fact about the capacities of the human mind. But it has major consequences for every aspect of philosophy. Metaphorical thought is the principal tool that makes philosophical insight possible, and that constrains the forms that philosophy can take.

To understand how fundamental metaphor is to our thinking, we must remember that human cognition is embodied:

We have inherited from the Western philosophical tradition a theory of faculty psychology, in which we have a "faculty" of reason that is separate from and independent of what we do with our bodies. In particular, reason is seen as independent of perception and bodily movement...

The evidence from cognitive science shows that classical faculty psychology is wrong. There is no such fully autonomous faculty of reason separate from and independent of bodily capacities such as perception and movement. The evidence supports, instead, an evolutionary view, in which reason uses and grows out of such bodily capacities.

Consider, for example, the fact that as neural beings we must categorize things:

We are neural beings. Our brains each have 100 billion neurons and 100 trillion synaptic connections. It is common in the brain for information to be passed from one dense ensemble of neurons to another via a relatively sparse set of connections. Whenever this happens, the pattern of activation distributed over the first set of neurons is too great to be represented in a one-to-one manner in the sparse set of connections. Therefore, the sparse set of connections necessarily groups together certain input patterns in mapping them across to the output ensemble. Whenever a neural ensemble provides the same output with different inputs, there is neural categorization.

To take a concrete example, each human eye has 100 million light-sensing cells, but only about 1 million fibers leading to the brain. Each incoming image must therefore be reduced in complexity by a factor of 100. That is, information in each fiber constitutes a "categorization" of the information from about 100 cells.

Moreover, almost all our categorizations are determined by the unconscious associative mind — outside our control and even our awareness — as we interact with the world. As Lakoff & Johnson note, "Even when we think we are deliberately forming new categories, our unconscious categories enter into our choice of possible conscious categories."

And because our categories are shaped not by a transcendent, universal faculty of reason but by the components of our sensorimotor system that process our interaction with the world, our concepts and categories end up being largely sensorimotor concepts and categories.

Here are some examples of metaphorical thought shaped by the sensorimotor system:

Important Is Big
Example: "Tomorrow is a big day."
Mapping: From importance to size.
Experience: As a child, finding that big things (e.g. parents) are important and can exert major forces on you and dominate your visual experience.

Intimacy Is Closeness
Example: "We've been close for years, but we're beginning to drift apart."
Mapping: From intimacy to physical proximity.
Experience: Being physically close to people you are intimate with.

Difficulties Are Burdens
Example: "She's weighed down by her responsibilities."
Mapping: From difficulty to muscular exertion.
Experience: The discomfort or disabling effect of lifting or carrying heavy objects.

More Is Up
Example: "Prices are high."
Mapping: From quantity to vertical orientation.
Experience: Observing the rise and fall of levels of piles and fluids as more is added or subtracted.

Categories Are Containers
Example: "Are tomatoes in the fruit or vegetable category?"
Mapping: From kinds to spatial location.
Experience: Observing that things that go together tend to be in the same bounded region.

Linear Scales Are Paths
Example: "John's intelligence goes way beyond Bill's."
Mapping: From degree to motion in space.
Experience: Observing the amount of progress made by an object.

Organization Is Physical Structure
Example: "How do the pieces of this theory fit together?"
Mapping: From abstract relationships to experience with physical objects.
Experience: Interacting with complex objects and attending to their structure.

States Are Locations
Example: "I'm close to being in a depression and the next thing that goes wrong will send me over the edge.
Mapping: From a subjective state to being in a bounded region of space.
Experience: Experiencing a certain state as correlated with a certain location (e.g. being cool under a tree, feeling secure in a bed).

Purposes Are Destinations
Example: "He'll ultimately be successful, but he isn't there yet."
Mapping: From achieving a purpose to reaching a destination in space.
Experience: Reaching destinations throughout everyday life and thereby achieving purposes (e.g. if you want food, you have to go to the fridge).

Actions Are Motions
Example: "I'm moving right along on the project."
Mapping: From action to moving your body through space.
Experience: The common action of moving yourself through space, especially in the early years of life when that is to some degree the only kind of action you can take.

Understanding Is Grasping
Example: "I've never been able to grasp transfinite numbers."
Mapping: From comprehension to object manipulation.
Experience: Getting information about an object by grasping and manipulating it.

As a neural being interacting with the world, you can't help but build up such "primary" metaphors:

If you are a normal human being, you inevitably acquire an enormous range of primary metaphors just by going about the world constantly moving and perceiving. Whenever a domain of subjective experience or judgment is coactivated regularly with a sensorimotor domain, permanent neural connections are established via synaptic weight changes. Those connections, which you have unconsciously formed by the thousands, provide inferential structure and qualitative experience activated in the sensorimotor system to the subjective domains they are associated with. Our enormous metaphoric conceptual system is thus built up by a process of neural selection. Certain neural connections between the activated source- and target-domain networks are randomly established at first and then have their synaptic weights increased through their recurrent firing. The more times those connections are activated, the more the weights are increased, until permanent connections are forged.

Primary metaphors are combined to build complex metaphors. For example, Actions Are Motions and Purposes Are Destinations are often combined to form a new metaphor:

A Purposeful Life is a Journey
Example: "She seems lost, without direction. She's fallen off track. She needs to find her purpose and get moving again."

Can we think without metaphor, then? Yes. Our concepts of so-called "basic level" objects (that we interact with in everyday experience) are often literal, as are sensorimotor concepts. Our concepts of "tree" (the thing that grows in dirt), "grasp" (holding an object), and "in" (in the spatial sense) are all literal. But when it comes to abstract reasoning or subjective judgment, we tend to think in metaphor. We can't help it.

Implications for philosophical method

What happens when we fail to realize that our thinking is metaphorical? Let's consider a famous example: Zeno's paradox of the arrow.

Zeno described time as a sequence of points along a timeline. Now, consider an arrow in flight. At any point on the timeline, the arrow is at some particular fixed location. At a later point on the timeline, the arrow is at a different location. But since the arrow is located at a single fixed place at every point in time, then where is the motion?

Suppose, Zeno argues, that time really is a sequence of points constituting a time line. Consider the flight of an arrow. At any point in time, the arrow is at some fixed location. At a later point, it is at another fixed location. The flight of the arrow would be like the sequence of still frames that make up a movie. Since the arrow is located at a single fixed place at every time, where, asks Zeno, is the motion?

The puzzle arises when you take the metaphor of time as discrete points along the space of a timeline as being literal:

Zeno's brilliance was to concoct an example that forced a contradiction upon us: [a contradiction between] literal motion and motion metaphorically conceptualized as a sequence of fixed locations at fixed points in time.

Moral concepts as metaphors

For a more detailed illustration of the philosophical implications of metaphorical thought, let's examine the metaphors that ground our moral concepts:

Morality is fundamentally seen as the enhancing of well-being, especially of others. For this reason, ...basic folk theories of what constitutes fundamental well-being form the grounding for systems of moral metaphors around the world. For example, since most people find it better to have enough wealth to live comfortably than to be impoverished, we are not surprised to find that well-being is conceptualized as wealth...

We all conceptualize well-being as wealth. We understand an increase in well-being as a gain and a decrease of well-being as a loss or a cost. We speak of profiting from an experience, of having a rich life, of investing in happiness, and of wasting our lives... If you do something good for me, then I owe you something, I am in your debt. If I do something equally good for you, then I have repaid you and we are even. The books are balanced.

Well-Being Is Wealth is not the only metaphor behind our moral thinking. Here are a few others:

Being Moral Is Being Upright; Being Immoral Is Being Low; Evil Is a Force
Example: "He's an upstanding citizen. She's on the up and up. She's as upright as they come. That was a low thing to do. He's underhanded. I would never stoop to such a thing. She fell from grace. She succumbed to the floods of emotion and the fires of passion. She didn't have enough moral backbone to stand up to evil."

How does the metaphorical nature of our moral concepts constrain moral philosophy? Let us contrast a traditional view of moral concepts with the view of moral concepts emerging from cognitive science:

The traditional view of moral concepts and reasoning says the following: Human reasoning is compartmentalized, depending on what aspects of experience it is directed to. There are scientific judgments, technical judgments, prudential judgments, aesthetic judgments, and ethical judgments. For each type of judgment, there is a corresponding distinct type of literal concept. Therefore, there exists a unique set of concepts that pertain only to ethical issues. These ethical concepts are literal and must be understood only "in themselves" or by virtue of their relations to other purely ethical concepts. Moral rules and principles are made up from purely ethical concepts like these, concepts such as good, right, duty, justice, and freedom. We use our reason to apply these ethical concepts and rules to concrete, actual situations in order to decide how we ought to act in a given case.

… [But] there is no set of pure moral concepts that could be understood "in themselves" or "on their own terms." Instead, we understand morality via mappings of structures from other aspects and domains of our experience: wealth, balance, order, boundaries, light/dark, beauty, strength, and so on. If our moral concepts are metaphorical, then their structure and logic come primarily from the source domains that ground the metaphors. We are thus understanding morality by means of structures drawn from a broad range of dimensions of human experience, including domains that are never considered by the traditional view to be "ethical" domains. In other words, the constraints on our moral reasoning are mostly imported from other conceptual domains and aspects of experience...

An explosion of productivity in moral psychology since Lakoff & Johnson's book was published has confirmed these claims. The convergence of evidence suggests that multiple competing systems contribute to our moral reasoning, and they engage many processes not unique to moral reasoning.

Once again, knowledge of cognitive science constrains philosophy:

This view of moral concepts as metaphoric profoundly calls into question the idea of a "pure" moral reason... [Moreover,] we do not have a monolithic, homogeneous, consistent set of moral concepts. For example, we have different, inconsistent, metaphorical structurings of our notion of well-being, and these are employed in moral reasoning.

Next post: Intuitions Aren't Shared That Way

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