Aristotle joined what he saw as the majority of his countrymen in condemning for selfishness those who sought only to profit themselves; but approved the self-love of the man of reason who sought to gain for himself the greatest share of what deserved social praise.
Adam Smith with the concept of the invisible hand saw the economic system as usefully channelling selfish self-interest to wider ends; while Locke based society upon the solitary individual, arguably opening the door for later thinkers like Ayn Rand to argue for selfishness as a social virtue and the root of social progress.
Roman Catholic philosopher Jacques Maritain opposed the latter view by way of the Aristotelian argument that framing the fundamental question of politics as a choice between altruism and selfishness is a basic and harmful mistake of modern states. Rather, cooperation ought to be the norm: human beings are by nature social animals, and so individual persons can only find their full good in and through pursuing the good of the community.
The contrast between self-affirmation and selfishness has become a conflictual arena in which the respective claims of individual/community is often played out – between parents and children or men and women, for example.
Psychoanalysts favor the development of a genuine sense of self, and may even speak of a healthy selfishness, as opposed to the self-occlusion of what Anna Freud called 'emotional surrender'.
Given two actors, oneself and someone else, there are four types of possible behavior directly impacting the welfare of the actors: selfishness, altruism, spite, and cooperation. Selfishness is harming someone else in order to help oneself; altruism is harming oneself in order to help someone else; spite is harming oneself in order to harm someone else; cooperation is helping someone else and also helping oneself. 
- Selfishness, The Free Dictionary, accessed on 17 December 2011
- Selfishness - meaning, reference.com, accessed on 23 April 2012
- C. S. Lewis, Surprised by Joy (1988) p. 116-7
- Aristotle, Ethics (1976) p. 301-3
- G. Gutting ed., The Cambridge Companion to Foucault (2003) p. 138-30
- Dante, Purgatorio (1971) p. 65
- Francis Bacon, The Essays (1985) p. 131
- Mandeville, The Fable of the Bees (1970) p. 410 and p. 81-3
- M. Skousen, The Big Three in Economics (2007) p. 29
- P. L. Nevins, The Politics of Selfishness (2010) p. xii-iii
- Maritain, Jacques (1973). The Person and the Common Good. Notre Dame, IN: University of Notre Dame Press. ISBN 978-0268002046.
- D. Goleman, Emotional Intelligence (1996) p. 104-10
- R. D. Laing, Self and Others (1969) p. 142-3
- What is Selfish?
- N. Symington, Narcissism (1993) p. 8
- Terence Real, I Don't Want to Talk About It (1997) p. 203-5
- Adam Phillips, On Flirtation (1994) p. 98
- A Theory of Justice (by John Rawls)
- The Evolution of Cooperation, Robert Axelrod, Basic Books, ISBN 0-465-02121-2