Sixteen Days

Barry Smith and Berit Brogaard

The Journal of Medicine and Philosophy , 28 (2003), 45-78. 

Abstract: When does a human being begin to exist? We argue that it is possible, through a combination of biological fact and philosophical analysis, to provide a definitive answer to this question. We lay down a set of conditions for being a human being, and we determine when, in the course of normal fetal development, these conditions are first satisfied. Issues dealt with along the way include: modes of substance-formation, twinning, the nature of the intra-uterine environment, and the nature of the relation between fetus and mother.

Short Version as Pdf File

Published Version


Assessing Ontologies:
The Question of Human Origins and Its Ethical Significance

Daniel Cohnitz and Barry Smith

Preprint version of a paper published in
E. Runggaldier and C. Kanzian (eds.), Persons: Persons - An Interdisciplinary Approach,
: öbv&hpt, 2003, 243–59.
Pdf file

See also papers on anatomical parthood here

Secondary Literature


Compiled 10/13/2012


Sixteen days? A reply to B. Smith and B. Brogaard on the beginning of human individuals

G Damschen, A Gómez-Lobo… - Journal of Medicine and …, 2006 - Taylor & Francis

When does a human being begin to exist? Barry Smith and Berit Brogaard have argued that 
it is possible, through a combination of biological fact and philosophical analysis, to provide 
a definitive answer to this question. In their view, a human individual begins to exist at ...

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[BOOK] The morality of embryo use

LM Guenin - 2008 -

Is it permissible to use a human embryo in stem cell research, or in general as a means for 
benefit of others? Acknowledging each embryo as an object of moral concern, Louis M. 
Guenin argues that it is morally permissible to decline intrauterine transfer of an embryo ...

Cited by 10 Related articles Library Search All 4 versions


[CITATION] Abortion: three perspectives

M Tooley, C Wolf-Devine, PE Devine - 2009 - Oxford University Press, USA

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The potential of the human embryo

MT Brown - Journal of Medicine and Philosophy, 2007 - Taylor & Francis

A higher order potential analysis of moral status clarifies the issues that divide Human Being 
Theorists who oppose embryo research from Person Theorists who favor embryo research. 
Higher order potential personhood is transitive if it is active, identity preserving and ...

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The European embryonic stem-cell debate and the difficulties of embryological Kantianism

A MauronB Baertschi - Journal of Medicine and Philosophy, 2004 - Taylor & Francis

As elsewhere, the ethical debate on embryonic stem cell research in Central Europe, 
especially Germany and Switzerland, involves controversy over the status of the human 
embryo. There is a distinctive Kantian flavor to the standard arguments however, and we ...

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“Life Begins When They Steal Your Bicycle”: CrossCultural Practices of Personhood at the Beginnings and Ends of Life

LM Morgan - The Journal of Law, Medicine & Ethics, 2006 - Wiley Online Library

A friend once told me I was wasting my time writing about cross-cultural perspectives on the 
beginnings of life.“Your work is interesting for its curiosity value,” he said,“but fundamentally 
worthless. What happens in other cultures is totally irrelevant to what is happening here.” ...

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Kant's Defense of Human Moral Status

P Kain - Journal of the History of Philosophy, 2009 -

Abstract: The determination of individual moral status is a central factor in the ethical 
evaluation of controversial practices such as elective abortion, human embryo-destructive 
research, and the care of the severely disabled and those in persistent vegetative states. ...

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[HTML] Ethics of Stem Cell Research

A Siegel - 2008 -

Human embryonic stem cell (HESC) research offers much hope for alleviating the human 
suffering brought on by the ravages of disease and injury. HESCs are characterized by their 
capacity for self-renewal and their ability to differentiate into all types of cells of the body. 

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Four queries concerning the metaphysics of early human embryogenesis

AA Howsepian - Journal of Medicine and Philosophy, 2008 -

Abstract In this essay, I attempt to provide answers to the following four queries concerning 
the metaphysics of early human embryogenesis.(1) Following its first cellular fission, is it 
coherent to claim that one and only one of two “blastomeric” twins of a human zygote is 

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D Marquis - Metaphilosophy, 2007 - Wiley Online Library

Abstract: Opponents of human embryonic stem cell (hESC) research claim that such 
research is incompatible with the moral principle that it is always wrong intentionally to end a 
human life. In this essay, I discuss how that principle might be revised so that it is subject ...

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Must we have full moral status throughout our existence? A reply to Alfonso Gómez-Lobo

D DeGrazia - Kennedy Institute of Ethics Journal, 2007 -

Abstract: Those who are morally opposed to abortion generally make several pivotal 
assumptions. This paper focuses on the assumption that we have full moral status 
throughout our existence. Coupled with the assumption that we come into existence at ...

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Metaphysics and Morality at the Boundaries of Life

P Robichaud - Journal of Medicine and Philosophy, 2006 - Taylor & Francis

This issue of The Journal of Medicine and Philosophy contains articles that are unified in 
their focus on issues related to the beginning and end of human life. Historically, a large 
measure of the bioethics literature is comprised of attempts to deal with ethical issues that ...

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Inviolability at any age

A Gómez-Lobo - Kennedy Institute of Ethics Journal, 2007 -

Abstract: This paper starts from three assumptions: that we are essentially human 
organisms, that we start to exist at conception, and that we retain our identity throughout our 
lives. The identity claim provides the background to argue that it is irrational for a person to ...

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[PDF] The Derives from relation in biomedical ontologies

M Brochhausen - Studies in Health Technology and Informatics, 2006 -

Abstract. This paper is part of the ongoing efforts within the framework of the Open 
Biomedical Ontologies (OBO) ontology library to optimize the treatment of relations in 
biomedical informatics. When ovum and sperm fuse to form a zygote, then the latter is ...

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Biological individuality

R De Sousa - Croatian journal of philosophy, 2005 -

The question What is an individual? goes back beyond Aristotle's discussion of substance to 
the Ionians' preoccupation with the paradox of change—the fact that if anything changes it 
must stay the same. Mere reflection on this fact and the common-sense notion of ...

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Fission, fusion, and the Simple View

C Tollefsen - Christian Bioethics, 2006 - Taylor & Francis

In this essay, I defend three Simple Views concerning human beings. First, that the human 
 is, from the one-cell stage onwards, a single unitary organism. Second, that when an 
embryo twins, it ceases to exist and two new embryos come into existence. And third, that ...

Cited by 1 Related articles BL Direct All 3 versions

[DOC] from

[DOC] Sortals and Human Beginnings

A Gómez-Lobo - Online paper accessed May, 2009 -

This is a question that has been asked many times in the past and is now asked again with 
renewed urgency. The reply I will give is certainly not new, but it will be reached invoking a 
piece of relatively recent evidence that I hope will also allow me to provide a fresh insight ...

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[HTML] from

Substance ontology cannot determine the moral status of embryos

J Morris - Journal of Medicine and Philosophy, 2012 -

Abstract Assigning the appropriate moral status to different stages of human development is 
an urgent problem in bioethics. Many philosophers have attempted to assess developmental 
events using strict ontological principles to determine when a developing entity becomes ...

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" Designer Babies" and Harm to Supernumerary Embryos

M Walker - American Philosophical Quarterly, 2008 - JSTOR

Ireimplantation genetic diagnosis"(PGD) refers to procedures used to test embryos in vi tro
Examination typically involves removal of one or two cells with a needle when the embryo is 
at the six-to ten-cell stage of development. Methods of assay, such as polymerase chain re ...

Related articles All 2 versions

“Other selves”: moral and legal proposals regarding the personhood of cryopreserved human embryos

EC Brugger - Theoretical medicine and bioethics, 2009 - Springer

Abstract This essay has two purposes. The first is to argue that our moral duties towards 
human embryos should be assessed in light of the Golden Rule by asking the normative 
question,“how would I want to be treated if I were an embryo?” Some reject the proposition ...

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[PDF] The beginning of life of a new human being from the scientific biological perspective and its bioethical implications

P Ventura-Juncá, MJ Santos - Biological Research, 2011 - SciELO Chile

ABSTRACT The issue of when the human life begins is a very important subject since it has 
a significant impact on the decisions that we have to take in relation to human beings in 
development, particularly human embryos. In this article we discuss some of the more ...

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Introduction: What Are Persons? What Is Valuable?

S Napier - Persons, Moral Worth, and Embryos, 2011 - Springer

As of this writing, if one searches Philosophers Index© under the term “abortion” one will get 
back 1, 485 total entries. If one limits the search to the past 10 years (2001–2011), one will 
get back 427 entries (almost 30% of the literature produced has been in the last 10 years). 

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Should we sacrifice embryos to cure people?

FD Lara - Human Affairs, 2012 - Springer

Abstract Medical stem cell research is currently the cause of much moral controversy. Those 
who would confer the same moral status to embryos as we do to humans consider that 
harvesting such embryonic cells entails sacrificing embryos. In this paper, the author ...


[CITATION] Conjoined Twins and the Biological Account of Personal Identity

R Koch - The Monist, 2008 -

PDC Homepage Home » Products » Purchase. LOGIN; PRODUCTS: All Products; Online
Resources; Journals & Series; Digital Media; Books & Reference Works. MEMBERSHIPS:
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[PDF] Is preimplantation genetic diagnosis ethically acceptable?

G Rager -

Preimplantation genetic diagnosis (PGD) implies severe risks for the mother and is not fully 
reliable in its diagnostic power. The main ethically relevant problem, however, is the fact that 
many embryos have to be generated in order to select the «suitable» ones, some of which ...

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[PDF] from

Fetal Interests, Fetal Persons, and Human Goods

C Tollefsen - Persons, Moral Worth, and Embryos, 2011 - Springer

The geography of the debate concerning practices destructive of the youngest members of 
the human species is by now rather well worked out. Of the questions to be answered, there 
is first the following: are you, the readers of this essay, and I, the author, and others ...

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