It is quite rare for philosophers to start investigating a new area, and a lot of the questions they explore have been around since ancient times. However, there is something they have only begun to look at closely in the last 15 years or so, which sits at the intersection of psychology and philosophy: inner speech.
Also known as the internal monologue, inner speech is the voice we hear in our minds when thinking or reading. Surprisingly, empirical research has found that not everyone has this inner voice, though the majority of us do.
Science and psychology have given it plenty of attention. We have known for over a century that the inner voice – especially when reading text – is accompanied by tiny movements of the larynx, showing a clear link between “internal” and “external” speech.
Philosophers have occasionally thought about inner speech before. The well known behaviourist Gilbert Ryle saw it as playing a key role in what philosophers call “self knowledge”. We learn about others by listening to what they say, and in his seminal 1949 book, The Concept of Mind, Ryle suggested that we are able to do the same to ourselves by “eavesdropping” on our own inner speech.
The phenomenon has made an appearance in other philosophical contexts, but it has not, until recently, been a topic of sustained attention in the field. Philosophers are now realising that psychology can only explain it up to a point: there are certain aspects of inner speech that can only be addressed by distinctively theoretical thinking.
Psychology vs philosophy
Inner speech has received a lot more attention from psychologists than philosophers over the years. Soviet psychologist Lev Vygotsky was a very influential figure on the subject.
Vygotsky noted – as we have all undoubtedly seen – that children of a certain age often speak to themselves aloud, but that they gradually stop as they grow older. He suggested that inner speech develops as this practice fades. According to Vygotsky, inner speech is simply external speech that has been internalised.
Many philosophers agree, but some see the phenomenon differently, as there are not, as far as we know, any other activities that we can perform both internally and externally. Some philosophers have thought that inner speech might not actually be speech but a mental representation of it.
Ray Jackendoff, for example, has suggested that we are imagining what speech sounds like when we produce inner speech, but doing so in a way which imitates how we would express ourselves if we were speaking aloud. We are not actually speaking, but simulating speech.
This is purely theoretical reasoning, but it does not aim to challenge or disprove psychological approaches. On the contrary, it enriches empirical research by adding a valuable new perspective.
Talking to ourselves?
One question we can answer, at least partly, is why we produce inner speech, even though no one else can hear it. There are a number of benefits.
Putting our thoughts into words can help to clarify our thoughts, and make them more precise. Sometimes we can only work out our true thoughts by saying them aloud. We often speak to others – or perhaps write our ideas down – to try and solve a problem or deal with emotions. Producing inner speech helps us to develop our own thoughts in a similar way.
There may be other benefits too. Making an existing thought or belief conscious by expressing it internally can help to advance a process of reasoning, even on everyday matters. “If I’m home by 6:30, I can cook dinner by 7:30,” you might say in inner speech. But this prompts the further thought, “Oh, but the game starts at 7. I’d better get takeaway instead.”
These answers, however, still leave a question open: are we actually talking to ourselves in the same way we talk to others? Or are we just talking?
Controlling the voice in your head
Another area with room for philosophical thinking is the question of whether producing inner speech is an action, or something that just happens.
When we physically speak aloud, it is typically an action: we can choose to do it, or not do it. The same cannot be said for inner speech, which is often unprompted, or even intrusive and undesired.
It can actually be hard to silence our internal monologue, and doing it at will is all but impossible. See for yourself, right now: concentrate on trying to think of nothing and stop producing inner speech. You will probably, paradoxically, find yourself producing more, and further efforts will only make it harder. Conditions such as stress, anxiety or depression also have proven psychological links to inner speech.
We can decide to produce a particular piece of inner speech – to “say” a word in our minds – but it often seems to happen without us doing anything at all.
What is an action?
In my research, I have argued that producing inner speech is almost never an action, though the question of what makes something an action is itself a topic of philosophical debate.
One prominent theory holds that actions are things that we can try to do, or that require effort. Producing inner speech often requires no effort, and as we have seen, we even struggle to stop it. This seems to indicate that it isn’t something we try to do, but that it just “happens”.
Other theories of action yield a similar result: inner speech almost never fits the definition.
A huge amount of philosophical work has been done on the subject of conscious experience in general. However, philosophers have not always paid attention to specific mental phenomena. Inner speech is a unique kind of conscious experience, which seems to involve a typically external activity – speaking – taking place in the mind. Investigating it will undoubtedly lead us down fascinating paths in years to come.