As individuals, we stand in a special relationship with time: we not only exist in time as a matter of pure fact, we are moreover aware of our cross-temporal identity and existence. It is particularly worthy of note that we conceive of ourselves as remaining the same persons for the whole of our lives although we quite obviously keep changing throughout - bodily and mentally. It seems perfectly normal to look at a photograph from one’s kindergarten age, to point at a tiny creature and to say: “That’s me”. Even if it is impossible to discover any significant surface similarity, no one would be really surprised by such a statement. How does such a paradoxical phenomenon arise?
That human organisms undergo continual change cannot provide a sufficient explanation. Apparently, different underlying factors are at work here: for one, the peculiarities of self-consciousness and the subjective perspective, and furthermore, the capacity of the autobiographical memory of individuals. To understand the complex phenomenon of personal identity better, one can try to extend particular philosophical approaches and combine them with findings, for instance, from empirical memory research.
The Subliminal Awareness of Being Present
In philosophy, self-consciousness is understood to be the capacity of making oneself the object of one’s own thinking and to establish relations with oneself through specific properties like bodily attributes or traits of character. This capacity is distinguished by particular features that have already been singled out to some extent by philosophers like Immanuel Kant. Manifold and variable states and ascriptions converge in the unitary subjective perspective of a person: we see, we hear, we smell, we have desires, beliefs, memories, emotions and we are conscious of moods. All these different phenomena condense to a homogeneous experience.
The subjective perspective rarely adopts a central position in all this; it much rather occurs in the form of a subliminal kind of awareness of being simply present. This subliminal awareness manifests itself in language, for example, in that the word “I” will normally always refer to the current speaker without any possibility of error on his or her part. Whoever says “I” always refers to himself or herself. Another function of the subjective perspective of experience is to have privileged access to some of one’s own mental states, in particular to sensations. Whoever suffers from a headache knows this only too well.
Reconstructing Entire Lifes
However, can this kind of clear self-ascription of states - this unity-supplying perspective - be expected to apply to temporally past states and situations without further qualification? It certainly does not come to a halt even if confronted with situations from the very distant past. When I claim to have been rebellious in my kindergarten time, I may very well be mistaken because I may, on the whole, have been a good child. Nevertheless, I am definitely speaking about myself at different points in time, and I am thus expressing indubitably an awareness of my cross-temporal identity.
Furthermore, such self-referential judgments concerning one’s own past also have a philosophically interesting structure when viewed from another angle: they are a manifestation of the fact that human individuals frequently enter into an interpretative relationship with the past periods of their lives and reconstruct their entire life as a more or less coherent whole. One tells oneself and others stories about oneself and thus designs an image of one’s own personality. Such stories deal with tussles in kindergarten, friendships, illnesses, moves to another town and travels. To have a biographical identity means to identify oneself with some of the earlier decisions, modes of behaviour, desires and predilections but at the same time to distance oneself deliberately from others.
Subjective perspective, unity of manifold experiences, temporal continuity, identity and biographical coherence: these philosophical aspects of personal identity may be enriched with the aid of empirical findings from memory research. One of the memory systems that is essential for personal identity is the autobiographical memory. It stores episodic recollections of incisive events in one’s life history, which one retraces within their appropriate contexts. Investigators of memory like Hans Markowitsch emphasise that such recollections make particular impact because the respective episodes are frequently permeated by emotional processes. For this reason, stable synaptic connections are established in the brain, which secure long-term storage: remote experiences of success, humiliations, the first love.
Studies also show that the autobiographical memory is socially structured. Recollections of earlier episodes are “aligned” and “synchronised” with the recollections of other people. One believes to have been rebellious during kindergarten times whereas one’s parents only recall a reasonably good child. Autobiographical recollection thus not only performs a corrective function but also accomplishes a high measure of social integration. The close relationship between self-identity, personality, temporal continuity and memory becomes even more apparent when looking at psychopathological cases of severe memory distortion.
An extreme example dating back to the 1950s is the patient known as H.M., whose hippocampus and amygdala, those parts of the brain associated with episodic memory, were surgically removed - a treatment that was actually supposed to cure the patient’s epilepsy. However, as an unintended side effect H.M. was no longer able to recall any of his former experiences such as events he had witnessed and things he had done in the past, nor could he remember any of the places he had been to or people whom he had met. Although he could still retrieve facts of general knowledge and other facts including his name, he completely lacked the sense of his temporal existence because he was deprived of his personal history.
Empirical research and philosophy together yield a more comprehensive picture of the peculiar relationship between individuals and their past. And so we achieve some deeper understanding of what it means that we are identical with the kindergarten kids that we were in a distant past.