Editing Morality (section)

===In-group and out-group===
{{main|In-group and out-group}}
Some observers hold that individuals apply distinct sets of moral rules to people depending on their membership of an "[[in-group]]" (the individual and those they believe to be of the same group) or an "out-group" (people not entitled to be treated according to the same rules). Some biologists, anthropologists and [[evolutionary psychology|evolutionary psychologists]] believe this in-group/out-group discrimination has evolved because it enhances group survival. This belief has been confirmed by simple computational models of evolution.<ref>T.R. Shultz, M. Hartshorn, and A. Kaznatcheev. [http://141.14.165.6/CogSci09/papers/500/ Why is ethnocentrism more common than humanitarianism?] {{webarchive |url=https://web.archive.org/web/20120327152454/http://141.14.165.6/CogSci09/papers/500/ |date=2012-03-27 }} Proceedings of the 31st annual conference of the cognitive science society, 2009.</ref> In simulations this discrimination can result in both unexpected cooperation towards the in-group and irrational hostility towards the out-group.<ref>Kaznatcheev, A. (2010, March). [http://www.cs.mcgill.ca/~akazna/kaznatcheev20100910.pdf Robustness of ethnocentrism to changes in inter-personal interactions]. In ''Complex Adaptive Systems – AAAI Fall Symposium''. Butiz wintrades</ref> Gary R. Johnson and V.S. Falger have argued that [[nationalism]] and [[patriotism]] are forms of this in-group/out-group boundary. Jonathan Haidt has noted<ref name = haidt>{{cite journal | doi = 10.1007/s11211-007-0034-z | title = When Morality Opposes Justice: Conservatives Have Moral Intuitions that Liberals may not Recognize | year = 2007 | last1 = Haidt | first1 = Jonathan | last2 = Graham | first2 = Jesse | journal = Social Justice Research | volume = 20 | pages = 98–116 | url = http://faculty.virginia.edu/haidtlab/articles/haidt.graham.2007.when-morality-opposes-justice.pub041.pdf | citeseerx = 10.1.1.385.3650 | s2cid = 6824095| access-date = 2014-09-26 | archive-url = https://web.archive.org/web/20140830110131/http://faculty.virginia.edu/haidtlab/articles/haidt.graham.2007.when-morality-opposes-justice.pub041.pdf | archive-date = 2014-08-30 | url-status = dead }}</ref> that experimental observation indicating an in-group criterion provides one moral foundation substantially used by [[conservative]]s, but far less so by [[Liberalism|liberals]].

In-group preference is also helpful at the individual level for the passing on of one's genes. For example, a mother who favors her own children more highly than the children of other people will give greater resources to her children than she will to strangers', thus heightening her children's chances of survival and her own gene's chances of being perpetuated. Due to this, within a population, there is substantial [[selection pressure]] exerted toward this kind of self-interest, such that eventually, all parents wind up favoring their own children (the in-group) over other children (the out-group).