Category: CBT

This article was first published in the July 2005 edition of the BACP magazine CPJ (now Therapy Today).

Republished with minor amendments.  Copyright © Donald Robertson, 2005.  All rights reserved.

The philosopher’s school is a doctor’s clinic. (Epictetus, 1995: 3.23.30)1

There is currently [2005] a growth of interest in the “practical” or psychotherapeutic aspects of classical philosophy. Academic experts have long perceived “Late” or “Roman” Stoicism (c. 1st – 2nd Century AD) as offering the most explicit system of therapeutic concepts and techniques to be found in classical literature.  This article seeks to introduce some of the basic principles of Stoic philosophy to an audience of psychotherapists and counsellors. We have found that therapists are often surprised at how relevant to their practice and strangely familiar Stoic ideas actually are.  Indeed, we hope to demonstrate that many modern theories of psychotherapy, counselling and personal development are ultimately indebted to this age-old but virtually forgotten therapeutic tradition.

The Origins & History of Stoicism

Stoicism is an ancient European school of philosophy, which incorporates a comprehensive system of therapeutic exercises. Zeno of Citium founded the school in Athens, as a “Socratic” sect, around 300 BC. However, Stoicism was more than just a “philosophy”, in the modern academic sense of the word, it was a far-reaching and long-standing cultural movement. 

 The historical boundaries are controversial, but it is safe to say that the Stoic school of philosophy can be situated within a broader philosophical tradition of “practical philosophy.”  That movement as a whole lasted from around the time of Pythagoras of Samos (c. 6th century BC) –who may be considered the original philosopher-therapist– to the superseding of pagan philosophy by Christian theology well over 1,000 years later. Following the closure of the great pagan academies by the Christian Emperor Justinian in 529 AD, the therapeutic practices of Stoicism and other philosophical systems survived only insofar as they were assimilated into orthodox Christian theology, i.e., barely at all.

 As a living tradition of philosophical practice Stoicism’s time was over. However, some of its concepts survived in literature and experienced various revivals, most notably the so-called “Neostoicism” of the Renaissance period, explaining the traces of Stoic thought in the work of such influential figures as Erasmus, John Calvin, Rene Descartes, William Shakespeare, John Milton, and Michel de Montaigne, to name but a few.  Even the royals, Queen Elizabeth I of England and King James I of England (VI of Scotland), were considered admirers of Stoic philosophy. More recently, Tom Wolfe, author of Bonfire of the Vanities (1987), published a novel called A Man in Full (1998) in which one of the lead characters adopts a philosophy of life based on the ancient Stoic Manual of Epictetus. Hollywood director Ridley Scott’s epic Gladiator (2000) depicts the last days of the Stoic emperor Marcus Aurelius (Richard Harris) and briefly alludes to the cardinal philosophical virtues and the Stoic notion of ‘contempt for death.’ 

It is worth noting, in this context, that the English language still retains evidence of the therapeutic dimension of philosophy. The adjective ‘philosophical’, among other things, still clearly alludes to the ancient ideal of emotional calm (ataraxia) and self-mastery (sophrosyne). This usage of ‘philosophical’ has also become virtually synonymous with the modern, popular meaning of ‘stoical.’

 philosophical. adj. 3. Calm in adversity.

 stoical. adj. Having or showing great self-control in adversity. (OUP, 1992: ‘philosophical’, ‘stoical’)2 

Indeed, Stoicism’s influence over our thought and language, usually unrecognised, endures right down to the present day, so much so that people are often surprised to find that many familiar clichés and proverbs are derived from Stoic philosophy – I call this its “déjà vu factor.”

Stoicism & Modern Psychotherapy/Counselling

Stoicism is fundamentally a philosophy of life independent of any political or religious dogmas. Some have seen it as comparable to a “European Buddhism” or “Western Yoga”, similar in appeal to Oriental systems of thought. Yet it is essentially agnostic, naturalistic, and European in character. Though we shall focus on the therapeutic dimension of Stoicism, it does encompass the possibility of certain metaphysical and spiritual themes, which provide the basis for a sophisticated kind of rational mysticism. Indeed, historically Stoicism evolved into the high mysticism of the last great pagan philosophical school, Neoplatonism, which was in turn assimilated into Christianity.

However, Stoicism is also the forgotten ancestor of our own psychotherapeutic tradition.  The modern history of psychotherapy begins in the early Victorian era with the development of hypnotherapy as a medico-psychological treatment, from which Freud subsequently developed psychoanalysis. Yet thousands of years earlier, it was common parlance to refer to philosophy as a “physician of the psyche” and for philosophers to employ therapeutic aims, concepts, techniques, and styles of working. For example, it’s now known that Freud derived his concept of katharsis (psychical “purification”) from a superficial reading of Aristotle. However, as a classical scholar himself, he might have been aware that the word was more commonly used as a technical term to describe the separation of mind from emotional attachment to external, material things. This notion of the need to “separate” and “purify” the subjective (self) from the objective (other), so fundamental to Stoic practice, pre-empts the basic psychoanalytic concept of projection, which both Jung, and later Klein, inferred was among the most fundamental of all Freud’s so-called ‘defence mechanisms.’ 

More recently, existential and cognitive therapies have drawn explicitly upon similar themes from classical philosophy. When existential therapists, following Heidegger, discuss the importance of an “authentic being-toward-death”, e.g., they are perpetuating one of the central methods of ancient philosophical therapy, the melete thanatou or “meditation upon death”, dramatically portrayed in Plato’s dialogues on the last days of Socrates. The “here and now” philosophy of Gestalt therapy is a figure of speech translating the Latin “hic et nunc”, one of the key themes of Stoic psychotherapy: returning awareness to the present moment. Albert Ellis, the founder of REBT, openly acknowledges his debt to Epictetus, the author of the therapeutic Manual of Stoicism; hence many students of REBT are already partially apprised of its connection with Stoic philosophy. The “ABC model” widely used in cognitive therapy is simply another re-iteration of the perennial philosophical notion of philosophical katharsis, i.e., separating out our subjective judgements from the external events to which they give emotive meaning. In this regard, Cognitive therapists repeatedly cite the famous quotation from the Manual of Epictetus: ‘It is not things themselves that disturb people but their judgments about those things.’ (Epictetus, 1995: §5)1

Nowadays thinkers are freely developing personal development systems and eclectic psychotherapeutic techniques which, often unknowingly, re-introduce key concepts and techniques from classical Western philosophy. Indeed, the many ways in which modern therapists are indebted to ancient philosophy would fill a book by themselves. We only offer a few examples of this intellectual debt to emphasise the point that all therapists, for the most part unwittingly, operate in the shadow of a very ancient therapeutic model. We still speak the language and use the methods of an ancient therapeutics, whether we realise it or not. 

The Basic Concepts of Stoicism

The name “Stoic” simply refers to the stoa poekile, the “painted porch” within which Zeno of Citium, the school’s founder, delivered his lectures and training. However, Stoicism has a more descriptive name, it is also called the “Natural Life” or “Following Nature”, and many variations of this phrase are used to describe the basic orientation of the system. The ancient historian of philosophy Diogenes Laertius writes, ‘the end [of Stoicism] turns out to be living in agreement with nature, taken as living in accordance both with one’s own nature and with the nature of the whole [universe]’ (Diogenes Laertius: 1964, VII: 88).3  In this, Diogenes is alluding to the central Stoic distinction between (internal) human nature, and the (external) Nature of the universe.  In fact, this basic ideal was interpreted as applying at three levels, Diogenes could have added, ‘living in accord with the nature of all mankind,’ because the Stoics believed that the individual self can only be understand as one part, or rather a ‘limb’, of the community of all people. Hence, we have a system of coherence at three levels of ‘nature’:

1.       Self.  Moral integrity, truthfulness, and personal authenticity
2.       Mankind.  Empathic understanding, social justice, philadelphia (“brotherly love”)
3.       Universe.  Being at one with life, with the All, with the totality of Nature

The Stoic Emperor, Marcus Aurelius, employs these three tiers of psychological relations in the therapy journal he kept, the famous Meditations, when he writes:  

Your own mind, the Mind of the universe, your neighbour’s mind –be prompt to explore them all.

Your own, so that you may shape it to justice [and authenticity]; the universe’s, that you may recollect what it is you are a part of; your neighbour’s, that you may understand whether it is informed by ignorance or knowledge, and also may recognise that it is kin to your own. (Marcus Aurelius: 1964, 9:22)4

Stoicism, therefore, is essentially a philosophy of being at one (homologoumenos), or in harmony with, the totality of life. As psychotherapy, it equates mental and emotional health with integration or a sense of “oneness” at these three levels of existence. This simple and intuitive threefold classification also provides the basic structure for applying Stoic psychotherapy, the ‘Threefold Rule of Life.’ 

The Threefold Rule of Life

Objective judgement, now, at this very moment [Logic].

Unselfish action, now, at this very moment [Ethics].

Willing acceptance –now, at this very moment– of all external events [Physics].

That’s all you need. (Marcus Aurelius: 2003, 9.6)5

The Stoics divided their philosophy into three branches: Logic, Ethics and Physics. It is important to realise that these words have now changed their meaning; indeed we will substitute “Metaphysics” for “Physics.” Greek philosophy in general also recognised four ‘cardinal virtues’: Truth, Justice, Temperance, and Fortitude.  These may correlate with the Threefold Rule, the disciplines of Judgement, Action, and of Fear and Desire, and with what we might term the three ‘Core Qualities’ of Stoicism: ‘Objectivity’, ‘Integrity’, and ‘Acceptance.’  Fortunately, for ham-fisted scholars trying to translate these ideas into plain English, we possess a beautifully concise and poetic expression of the Threefold Rule,

“The Serenity Prayer”

God,

Grant me the Serenity

to accept the things I cannot change;

Courage to change the things I can;

and Wisdom to know the difference.

This is the so-called “Serenity Prayer” of the Twelve Step Programme of Alcoholics Anonymous. Although the earliest records attribute it to the late Victorian era, it is so obviously consistent with Stoic philosophy that it is tempting to speculate whether it originates in a much earlier source. In fact, some writers claim that it is based upon the work of the early medieval philosopher Boethius, author of The Consolations of Philosophy, though I have been unable to verify this. 

This, in a nutshell, is the essence of Stoic philosophy; though precisely because of its simplicity it does not give full expression to the enormous breadth of ideas which that system contains. It expresses one of the most fundamental principles of Stoicism: ‘to know the difference between what depends upon me and what does not.’ The Stoics mean by this precisely the distinction we have made between that which is internal and directly subject to my will, and that which I must accept as external and beyond my immediate control, i.e., wholly, or even partially, contingent upon external events.

What, then, should we have at hand upon [challenging] situations? Why, what else than to know what is mine, and what is not mine, what is within my power, and what is not. (Epictetus: 1995, 1.1.21)1

The Threefold Rule of Life

The previous section considered the Stoicism’s history and its relation to modern psychotherapy and counselling. We explained that the grand maxim of Stoic therapy is ‘To follow Nature.’  The first logical step on this path being to distinguish between our own internal nature, the field of Stoic Ethics, and the external Nature of the universe as a whole, the domain of (Meta-) Physics; Stoic Logic aims to make this distinction objectively. This is the Threefold Rule of Life, the basic psychotherapeutic structure presupposed in classical Stoic literature.  Marcus, e.g., exhorts himself to: “Apply them constantly, to everything that happens: Physics, Ethics, Logic” (Marcus Aurelius: 2003, 8:13) 5  We now proceed to examine each of these therapeutic disciplines in turn.

Logic: The Discipline of Judgement

And progress for a rational mind means not accepting falsehood or uncertainty in its perceptions […]. (Marcus Aurelius: 2003, 8:7)5

We can equate the supreme classical virtue of ‘Truth’ with the core quality which I call ‘Stoic Objectivity’, the ability to separate internal from external nature.  In one sense, the heart of Stoic Logic is ‘know thyself’, the legendary maxim inscribed at the Oracle of Apollo in Delphi. However, such knowledge takes on a special character in Stoicism; true knowledge is seen as precisely this ability to clarify the boundaries of the inner self. That is, to continually distinguish, in the present moment, between internal and external nature, i.e., between mind and matter.  As Epictetus says, ‘And to become educated [trained in philosophy] means just this, to learn what things are our, and what are not.’ (Epictetus: 1995, 4.5.7). We can picture this demarcation as the drawing of an imaginary boundary, a circle around the limits of the true self. Indeed, the Stoics described the perfectly circumscribed mind of the ideal Sage as ‘fencing itself off’, an unassailable ‘inner citadel’, and a ‘sphere in perfect equilibrium.’

The ancients generally defined the psyche in terms of activity, as ‘that which moves itself.’ Hence, for Stoicism, the essence of the self is the autonomous action of our freewill: our intentions, thoughts, and decisions. This is a deeply existential view of the self; man is essentially freewill in action, everything else is extraneous to the self. The attitude we call ‘Stoic Mindfulness’ (prosoche), then, means constant self-awareness of the movements of the mind, assuming full responsibility for our own judgements, actions, fears and desires. 

Mindfulness also entails owning our thoughts, re-owning our projections, and suspending all value-laden or emotive judgements. Our thoughts project meaning and form onto our perceptions, by separating the two we attain Truth and Objectivity.  Moreover, the key therapeutic slogan of Stoic Logic is: ‘It is not things that disturb people but their judgements about things.’ (Epictetus: 1995, §5)1  Hence, John Milton’s Satan boasts, ‘The mind is its own place, and in itself can make a heaven of hell, a hell of heaven.’ (Milton, :I, 254)6 As Shakespeare’s Hamlet exclaims: ‘There’s nothing good or bad but thinking makes it so!’ (Shakespeare, 1994, Act 2, Scene 2)7 Marcus Aurelius provides many practical examples of this principle in his therapeutic journal: 

[Remember that] this noble vintage is grape juice, and the purple robes [of imperial office] are sheep wool dyed with shellfish blood. […] Perceptions like that –latching onto things and piercing through them, so we see what they really are. That’s what we need to do all the time –all through our lives when things lay claim to our trust– to lay them bare and see how pointless they are, to strip away the legend that encrusts them. (Marcus Aurelius: 2003, 6:13)5

[Assent to] nothing but what you get from first impressions. That someone has insulted you, for instance. That –but not that it’s done you any harm. The fact that my son is sick –that I can see. But “that he might die of it,” no. Stick with first impressions. Don’t extrapolate. And nothing can happen to you. (Marcus Aurelius: 2004, 8:49)5

We ascertain the truth when we acknowledge and suspend our own prejudices and let the facts speak for themselves. This technique of stripping things down to their essence, phrased in a few words, is known by scholars as ‘essential analysis.’ Its goal is called ‘objective representation’ (phantasia kataleptike), to this alone the Sage’s judgement assents. 

At a practical level, the Discipline of Judgement was achieved by a variety of therapeutic methods. For instance, sophisticated rhetorical techniques and verbal formulae –i.e., language patterns– were used to reframe perceptions. Visualisation was employed, e.g., in imagining the presence of an ideal Sage, accompanying the student as a mentor and observer. Moreover, the therapy was conducted in three modes which happen to correspond to the main surviving examples of Roman Stoic literature.

Although the Discipline of Judgement was the logical cornerstone of the whole therapeutic system, practical training began with the two disciplines to which we now turn. 

Ethics: The Discipline of Action

[Follow] your own nature, through your actions. Everything has to do what it was made for. […] Now, the main thing we were made for is to work with others. (Marcus Aurelius, 2003: 7:55)5 

Stoic Integrity means to act at one with one’s own innermost nature and the nature of all mankind. The cardinal virtue of ‘Dikaiosyne’ has a dual meaning, it translates as either ‘personal authenticity’ or ‘social justice.’ Likewise, the Discipline of Action involves taking responsibility for all of our actions and directing them toward the solitary goal of reconciling personal moral integrity with love for all mankind.  Our sense of identity determines self-interest and therefore Ethics, because ‘wherever “I” and “mine” are placed, to there the creature inevitably inclines.’ (Epictetus: 1995, 2.22.18)1 For the Sage, therefore, there is no conflict between self-interest and social-interest because he identifies his own nature with the nature of all mankind. This sense of existential kinship is exercised by deliberately practising ‘brotherly love’ (philadelphia) and ‘exploring the minds of others.’ The striking parallel with the core counselling qualities of ‘congruence’, ‘unconditional positive regard’, and ’empathic understanding’ espoused by Carl Rogers will be obvious to any counsellor.  Motivation comes by making an affirmation of the first principle of Stoic moral psychology: ‘The good man is always happy.’ They distinguish sharply between sensory ‘pleasure’ (hedone) which is superficial insofar as it depends upon external factors, and ‘happiness’ (eudaimonia) which comes purely from doing the right thing, i.e., Integrity.  

Your integrity is your own; who can take it from you? Who but yourself will prevent you from using it? When you are eager for what is not your own, you lose that very thing. (Epictetus: 1995, 1.25.3)1

Epictetus elaborates, ‘nothing is of concern to us except our volition.’ The Sage, therefore, renounces attachment to material possessions and invests happiness solely in what is always within his grasp, moral integrity.  However, the Stoics recognised this was an idealistic vision. For practical purposes they distinguish between the absolute value of internal acts and the relative value of external goods. For example, physical health is considered a natural thing to desire and worth having, however, its value is secondary and derivative. That is, physical health is worth having only insofar as it contributes to moral integrity. Yet the Stoics believed that in extreme circumstances even death could be a rational choice. The archetypal example being Socrates, who famously accepted forced suicide rather than accept the trumped-up charges made against him in court – choosing Stoic Integrity over life. This solitary existential decision made him a legendary martyr, and effectively guaranteed philosophy a place at the heart of Western civilisation for posterity.

Some of the Stoics’ ethical views may seem challenging, even radical. However, their “Ethics” was not about moralising, in the modern sense, but something more akin to a system of personal development. Classical philosophy in general predicated its ethics on a notion of enlightened self-interest, which aims for a state of personal fulfilment and happiness. Hence, Aristotle refers to ethics as ethike arete, the science of ‘character excellence.’ Our moral character (ethos) is constituted by the principles of action which we develop into habits.

[Philosophy is] doing what human nature requires. […] Through first principles. Which should govern your intentions and your actions.’ (Marcus Aurelius: 2003, 8:1)5 

The process of ‘essential analysis’ central to Stoic Logic also creates the pithy slogans typical of their Ethics, e.g., “Seize the day”, “Indifference to indifferent things”, etc.  Contemplation, repetition, and memorisation of such principles of action (dogmata) was a key psychotherapeutic technique, as can be seen from the journal of Marcus Aurelius. Hence, these statements were used as autosuggestions, or affirmations, composing a ‘principle-centred’ and inherently therapeutic Ethics.

Metaphysics: The Discipline of Fear & Desire

Reasonable nature is indeed following its proper path if […] it has desire and aversion only for that which depends on us; while it joyfully greets all that which is granted to it by universal Nature. (Marcus Aurelius: 2003, 8:7)5 

Stoic Acceptance means living at one with the external Nature of the universe. The cardinal virtue of ‘Temperance’ means mastering our desire for sensory pleasure, that of ‘Fortitude’ the conquest of our fear of pain and death. Hence, this discipline is about controlling pathos, or emotion. The Stoics believed that both fear (or emotional ‘aversion’) and desire result from excessive emotional attachment; the attitude of the Sage toward external things, therefore, is one of serene non-attachment. The primal and underlying fear which the Stoic seeks to conquer is that of death. ‘The breast from which you have banished the dread of death’, counsels Seneca, ‘no fear will dare to enter.’ (Seneca: 1997, 19)8. Contemplating the transience of life was a standard therapeutic technique of classical philosophy in general.  Indeed, Socrates famously insisted that all philosophy is preparation for death. In the wake of military victory, ancient Roman generals were followed by assistants whispering “memento mori” in their ears: “Remember you must die!” (cf. Discourses 3.24.84-8). Traditionally, many clocks and watches carried Latin inscriptions meant for the same purpose, typically the tempus fugit (‘time flies’), of the Roman poets.

This philosophical theme spawned a vast genre of the same name in the history of art. Examples of memento mori are countless, from the human skulls and wilting flowers of classical Vanitas painting to the animal cadavers of Damien Hirst, all confront us with coolly dispassionate reminders of our own mortality. That most iconic of all Shakespearean images, black-clad Hamlet contemplating the skull of his jester Yorick, affectionately parodies the philosophical practice of meditation on death. The practice of non-attachment and conquering death-anxiety is basically the application of Metaphysics. The original Stoic Metaphysics was wedded to pagan theology, however, belief in God is not essential to Stoicism. As a system of psychotherapy it stands apart from any particular religion or set of spiritual beliefs, and is easily adapted to modern agnostic or even atheistic perspectives. Nevertheless, the early Stoics were mainly pantheists who believed that the totality of the physical universe is simply the Body of God, and the object of His eternal meditation. The aim of their mysticism is simply union with the Mind of God (‘the One’). Hence, it was natural for them, like many earlier philosophers, to infer that by visualising the universe (‘the All’) they attained a Godlike point-of-view. From this God’s-eye perspective, the key concepts of Stoic Metaphysics became more apparent; namely, the unity, transience, and interdependence of all material things. 

The world as a living being –one nature, one soul. Keep that in mind. And how everything feeds into that single experience, moves with a single motion. And how everything helps produce everything else. Spun and woven together. […] Time is a river, a violent current of events, glimpsed once and already carried past us, and another follows and is gone. (Marcus Aurelius: 2003, 4:40-43)5 

For the Stoic, the universe viewed in its entirety is objective reality. Our normal, embodied and earthbound perspective necessarily distorts reality because it is confined to a tiny corner of the universe. Hence, ‘the All is One’, and the totality is the only authentic reality.

Modern scholars call this meditation exercise the ‘View from Above’, and variations of it abound in ancient literature. Sometimes it entails contemplation of the entire universe as though contained in a sphere. Typically though, philosophers attempted to visualise the Earth seen from outer space, a technique which created profound emotional detachment and tranquillity.  Support for this ancient therapeutic intuition comes from the numerous observations of astronauts, who describe the actual experience of seeing the world from space in remarkably similar terms. General Thomas Stafford, commander of the NASA Apollo 10 project, reports:

[From space] you have an almost dispassionate platform -remote, Olympian- and yet [seeing the Earth from up there is] so moving that you can hardly believe how emotionally attached you are to those rough patterns shifting steadily below. (Kevin W. Kelley (ed.), 1988)9 

Marcus Aurelius writes of the ideal Stoic attitude in identical terms: ‘To be free of passion and yet full of love.’ (Marcus Aurelius, 7.9)5 Coincidentally, this meditation exercise may well have evolved out of attempts to visualise the same perspective, of Zeus looking down from Mount Olympus, that General Stafford metaphorically alludes to.  This attitude of serene affection is the goal of the Discipline of Fear and Desire. It is for this reason that Stoicism viewed the practice of pre-scientific, or ‘phenomenological’ physics as a therapy of ‘fear and desire’ in its own right.

Conclusion

[After training in Freudian analysis] I gradually turned more and more to accumulated wisdom in the fields of philosophy. After all, philosophers have been thinking of some of the same issues that we have for the past 2,000 years and I’ve drawn a lot from philosophical insights. (Dr. Irvin Yalom, interviewed in the CPJ, July 2004: 8)

Why does this philosophy stuff matter so much to so many therapists and counsellors?  First, many people simply prefer the stylistic beauty and philosophical depth of classical literature over modern alternatives. Stoicism has demonstrated a perennial appeal enduring more than two millennia. For example, former US President Bill Clinton recently named the Meditations of Marcus Aurelius as his most treasured read. 

Second, many therapists feel the need for a broader philosophical framework. Psychoanalysis, perhaps Marxism, and to some degree religions such as Buddhism and Christianity offer an established ideological basis for therapy practice. Stoicism, on the other hand, offers a viable philosophy of psychotherapy which is not inherently wedded to religious or political dogmas. Ironically, in relation to modern, brief psychotherapy Stoic philosophy proves significantly more relevant than traditional Freudian theory.

Third, the Stoic system contains basic therapeutic principles and techniques not found in modern therapy, which are still relevant and applicable today. Indeed, we have only scraped the surface of Stoic psychotherapy in this article. In particular there are a number of rhetorical strategies and therapeutic interventions –visualisation techniques, etc.– which are not discussed here but which we have found of considerable use in working with clients and workshop participants.  Hence, we would encourage those with an interest in this area to research the primary texts themselves. There is still a great deal to be learned from the ancient forebears of psychotherapy. 

References

1 Epictetus The discourses, the handbook, fragments. London: Everyman, 1995.

2 Oxford University Press The Oxford Dictionary of Current English. Oxford: OUP, 1992.

3 Laertius, Diogenes Lives of the philosophers. H.S. Long (ed.) Oxford: OUP, 1964.

4 Aurelius, Marcus Meditations. London: Penguin, 1964.

5 Aurelius, Marcus Meditations: living, dying and the good life. London: Phoenix, 2003.

6 Milton, John Paradise Lost. Oxford: OUP, 2004.

7 Shakespeare, William Hamlet. London: Penguin:, 1994.

8 Seneca, Lucius Annaeus Consolation to Helvia, in Dialogues and letters. London: Penguin, 1997.

9 Kevin W. Kelley (ed.) The Home Planet. Boston: Addison-Wesley 1988