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Introduction
Hello, fellow philosophy enthusiasts and curious minds! Today, I’m excited to share with you a piece of my academic journey. What you’re about to read is an adaptation of a small part of the introduction to my master’s thesis in philosophy, written in 2020. I’ve decided to post some of this academic content as a way to revisit philosophical thinking and to get back into the rhythm of writing.
As someone who’s been away from the academic world for a while, I find that returning to these complex ideas helps to sharpen my mind and reinvigorate my love for philosophical discourse. By sharing this with you, I hope not only to offer some insights into a fascinating area of philosophy of mind but also inspire others who, like me, are looking to reconnect with their academic roots.
So, let’s dive into the intriguing world of mental states, exploring two critical features that have long puzzled philosophers and cognitive scientists alike: intentionality and phenomenal character.
The Dichotomy of Mental States
When we examine the realm of mental states, we find that they generally fall into two main categories: sensations (or experiences) and intentional states. This distinction, while not always clear-cut, provides a useful framework for our discussion.
Sensations
Sensations encompass a wide range of experiences, from bodily sensations like pain, tickles, or nausea to perceptual impressions such as seeing a vibrant color, hearing a loud trumpet, or tasting a sweet apple.
What unifies these diverse experiences is their qualitative character - that ineffable “what it is like” to have that particular sensation. This qualitative aspect, often referred to as qualia in philosophical discourse, is what defines our subjective experience of the world.
INFO
- Sensations: bodily sensations such as tickles, pain, nausea, and perceptual impressions like color, smell, and taste impressions.
- The critical feature of sensations: Their qualitative character, the fact that it is always in a certain way or feels a certain way to have a sensation.
Intentional States
On the other hand, intentional states include familiar mental phenomena like beliefs, desires, fears, and expectations.
The term “intentionality,” as used here following Brentano, is a philosophical technical term with a special meaning. It does not refer to the everyday understanding of deliberateness, but rather to the directedness towards an object (often called “aboutness”). A mental state is called “intentional” when it has an intentional object or semantic content.
Intentionality is
characteristic exclusively of mental phenomena. No physical phenomenon manifests anything like it.1
Consciousness is always “consciousness of”, and this “of-ness” is what characterizes intentional states. Intentions and desires thus also belong to the group of intentional states, as they too have an object or content. However, they form only one type of intentional state among many others; they do not have a special status with regard to the problem of intentionality discussed here.2
Unlike sensations, these states are characterized primarily by their intentionality — they are always about something. When we believe, desire, fear, or expect, our mental state is directed towards some object or state of affairs. This “aboutness” or directedness is the hallmark of intentionality.
The Challenge of Integration
Now, you might wonder why these mental states pose such a challenge for integration into a scientific worldview. The crux of the matter lies in the unique properties of both sensations and intentional states.
For sensations, the primary stumbling block is their qualitative character. How can we reconcile the subjective, felt experience of seeing a vivid green meadow or tasting a sweet apple with the objective, physical states of our brain? It seems counterintuitive, even impossible to many, that mere brain states could possess these rich, qualitative characteristics. This intuition has led many philosophers to doubt whether sensations can be reduced to or fully explained by brain states.
Intentional states, while not characterized by the same kind of qualitative experience, present their own set of challenges. First and foremost is the issue of semantic content. How can a physical state, like a particular configuration of neurons, be about something? How can it have meaning or representational content? This question of how physical systems can give rise to semantic properties has been a persistent thorn in the side of physicalist theories of mind.
But the challenges don’t stop there. Intentional states exhibit another peculiar feature: the causal relationships between them often respect rationality principles and semantic relationships between their contents.
Let’s unpack this with an example. Imagine you have a desire for a cool beer and a belief that there’s a bottle of Tegernseer in the fridge. These mental states might cause you to walk to the kitchen and retrieve the beer from the fridge. But notice that this action isn’t just caused by your mental states — it’s also rational given those states.
It would be neither rational nor likely for these same mental states to cause you to go to the kitchen sink and drink a glass of water instead. This parallelism between causal relations and rationality principles extends to beliefs as well. If you believe that both Peter and Lena are coming to the party, this will typically cause you to believe that Peter is coming to the party. This causal relationship mirrors the logical relationship between these propositions — it’s rational to believe Peter is coming if you believe both Peter and Lena are coming.
INFO
- Intentional states: beliefs, desires, fears, expectations, and other mental states that are directed towards an object or content.
- The critical features of intentional states:
- Their intentionality, i.e., the fact that they always have semantic content.
- The fact that causal relations between intentional states often respect principles of rationality or semantic relations between their contents.
The Parallelism Puzzle
This remarkable parallelism between causal relations and rationality principles presents yet another puzzle for those seeking to integrate mental states into a scientific worldview. How can the brain states that supposedly correspond to our desires and beliefs consistently cause actions that are rational in light of those mental states?
How can the brain state corresponding to the belief that p typically cause brain states corresponding to beliefs that are rational to hold if one believes that p?
These questions highlight the deep challenges we face in understanding the relationship between our mental lives and the physical world. They push us to reconsider our conceptions of causation, rationality, and the nature of the mind itself.
In conclusion, the integration of mental states — both sensations and intentional states — into a scientific worldview remains one of the most intriguing and challenging problems in philosophy of mind. The qualitative character of sensations, the semantic content of intentional states, and the rational causal relations between intentional states all pose significant difficulties for a purely physicalist account of the mind. As we continue to grapple with these issues, we push the boundaries of our understanding of consciousness, cognition, and the nature of reality itself.
Further Reading
I highly recommend reading through the relevent pages on the Stanford Encyclopedia of Philosophy for a more in-depth exploration of these topics: