Death/Killing/Human/P. Singer: We have seen that it is not dependent on belonging to a species, that it is wrong to allow suffering and pain to a being or to kill it. The biological limits of our own species have no ethical significance.
However, this attitude differs from the general attitude in our society. In history, Homo Sapiens's membership of the species was not enough to protect the life of someone, as the fate of slaves and barbarians shows.
Plato and Aristotle thought that the state should promote the right to kill deformed children. (Plato: The State, bk. V, 460c, Aristotle: Politica, bk. VII, p. 1335b).
The famous texts of the law, attributed to Solon and Lykurg, are similar. Our current views are more derived from Christianity. They have to do with the belief in immortality.
Another Christian argument was that we are God's property and that it is God's decision whether we live or die.
Death/Killing/Thomas Aquinas/Peter Singer: according to Thomas, killing a human being is a sin against God in the sense that killing a slave is a sin against its owner. On the other hand, God gave the animals to the human at his disposal. (Thomas Aquinas, Summa Theologica, II, ii, 64, art.)
Death/Hedonist Utilitarianism/P. Singer: since there are no needs for the future after death, according to hedonistic utilitarianism there is no direct relevance of the term "person" (with a sense of the future) in relation to the falsehood of killing. Indirectly, however, there is: in relation to the fears that I can have as a living being.
The care for one's own future is now what distinguishes the person from other living beings._____________Explanation of symbols: Roman numerals indicate the source, arabic numerals indicate the page number. The corresponding books are indicated on the right hand side. ((s)…): Comment by the sender of the contribution. The note [Author1]Vs[Author2] or [Author]Vs[term] is an addition from the Dictionary of Arguments. If a German edition is specified, the page numbers refer to this edition.
Practical Ethics (Third Edition) Cambridge 2011
The Most Good You Can Do: How Effective Altruism is Changing Ideas About Living Ethically. New Haven 2015