Jonathan Haidt is a recent a social psychologist that has written several good books, one of which deals heavly with this subject and was a 2012 best seller The Righteous Mind: Why Good People Are Divided by Politics and Religion. Now when I say social psychologist I am referring to the study of people and people's behavior in a group, how people's thoughts, feelings, and behaviors are influenced by the actual, imagined, or implied presence of others. In contrast a sociologist is the study of groups of people and how groups of people interact with other groups of people and with society at large.

He asks questions like is it moral or immoral to eat your family dog?

Perhaps your family is starving?

Perhaps the dog died of old age, well then is it moral or immoral to eat your family dog after it died? And so on...

He also has some famous questions involving chickens instead of pet dogs.

But his research shows that moral psychology is usually concerned with 5 or 6 things and that we have different types of morality and human beings have 5 or 6 moral foundations and we then build more complicated morality with these 5 or 6 moral frameworks as the foundational materials.

And since people can have different preferences, or even different styles for these 5 or 6 moral foundations it can lead to very different answers on ethical and moral quandries. That everybody can think they are doing the right thing.

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So you assume the body is sacred. In good faith I am going to challenge this position out of respect but then argue my interpetation may be just as valid.

So the body is sacred, yet lets use a metaphor to talk about how the body changes throughout time. Ship of Theseus also known as Theseus's paradox is a 2000 year old metaphor created by Platarch that is a good metaphor to use. Note the metaphor is actually older than 2000 years for Heraclitus and Plato talked about it as well but they did not specifically call it the Ship of Theseus.

So Theseus was a founder hero that slayed the Minotaur. After his journeys he brought his ship back to Athens and it was preserved as a monument in the city of Athens. It was required after Theseus journey for the ship to be sent back into the waters of the Aegean Sea and sailed to the Island of Delos, the birthplace of Apollo and Artemis where Leto hid from Hera after Leto and Zeus had sex and Leto was pregnant.

Since the ship was to be seaworthy for hundreds of years it was constantly repaired, and probably most of the ship is not with the original parts and for the sake of argument lets assume each plank of the ship was replaced. Is it still the ship of Theseus, or is it another ship?

The human body is much the same way. The original form you were born from your mother was probably 8 lbs more or less if it was a 40 week pregnancy and not early. Yet most adults are a 100 to 200 lbs of weight and the matter inside the human body is constantly changing. Where are the matter that is sacred vs the matter that is not.

In the Christian tradition we assume the body is still the essence of the soul due to some lines from Judaism where you will rise from the dead with your old body. Yet in other philosophies and religions this was not always the case including other religions in the fertile crescent.

In Japan there is a famous religious ritual where they rebuild a temple yearly to show that the world is constantly changing yet part of the essence is the same even if its not exactly the same

https://en.wikipedia.org/wiki/Ise_Grand_Shrine

There is a wonderful scene in House of Cards Season 3 involving a Sand Mandala. The wife gets the meaning of the Sand Mandala, but Francis Underwood does not truly understand the significance per his actions in Season 3. This link I am about to do has no spoilers but shows the sand mandala with some music

https://www.youtube.com/watch?v=5HhInqnBXxw

This is a buddhist ritual of creation followed by ritual distruction to remind people of the nature of things is change. Now while the sand mandala itself its a tibetian buddhist thing the concept of mandalas are both hindu and buddhist

https://en.wikipedia.org/wiki/Sand_mandala

In fact this is a theme in Judaism and Christianity with talking about the dust you are and dust you shall return in Genesis Chapter 3 and the whole book of the old testament Ecclesiastes deals with this.

Most people are not familiar with Ecclesiastes even though it is part of the canon in all forms of christianity as part of the old testament.

https://en.wikipedia.org/wiki/Ecclesiastes

The subject of the book is philosophy and the nature of human life and the meaning of life. Many metaphors and idioms can be traced back to this book. Such as there is nothing new under the sun.

The author talks about how nothing of earth is permanent, dust you are dust you shall return. Yet while the nature of man's things we make may just be hevel (mere breath) of man since it will all fade away some things may remain.

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Now many religions and traditions talk about it is the memory, the will, the culture, etc that is what is truly sacred and not the physical body. Now Judaism talks and says the body is important and sacred but it is the soul that is more important. The breath of life is the continuous aspect of the soul / spirit of judaism. Similar things can be seen in numerous other religions one of which is Ancient Egyptian but there are far more recent examples of this.

Now Judaism believes human beings are 3 things. Physical beings, social beings, and ethical beings. That the breath of life was given to us, but breath is not just taking in air but also expelling it, and that you need to live an ethical life and breathe in and out and there is a proper way of living where you are in communion of god.

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So perhaps the old woman wanted her will to be done and that this was the true sacred act and not the sacred body that was sacred but now strip of life it is no longer sacred.

But even if her body is no longer sacred her will is sacred and the will recognizes the bodies of living human beings are sacred and thus she wants to share herself in a communion to help others to give back.

So to ask again is it morally ethical to eat your dog? Some say it would be better to bury your dog while others may say it is sharing with the family.