Recently the discussion had been brought up about modern Druidic ethics and how - or even if - the concept of "harm none" fits in to a Druid's ethics. Some people feel strongly that a modern Druid should adhere to an ethical view that avoids any harm to others, although it varies between avoiding all harm and avoiding harm to other people. In contrast other people feel that modern Druids should preserve the best of the ancient Celtic views, including ethics.
My own opinion tends to agree with the second school of thought. I believe that as Druids in a modern world we are best served, and we best serve the ancient Druids memory, by learning what the ancient Druids, and to a greater degree the Celts, believed and finding the best ways to adapt that to our own time. Otherwise our ethics are not those of Celtic polytheists or Druids, but simply modern (or post modern) ethics; this is neither right nor wrong in itself, but as Druids I believe our ethics should be those of Druids.
Let's begin by looking at some of what we know of the ancient Druids and of Celtic morality. There are several examples in Irish lore that support the idea that violence was seen as being a necessity at times. From the triads of Ireland: "Three deaths that are better than life: the death of a salmon, the death of a
fat pig, the death of a robber" and: "Three bloodsheds that need not be impugned: the bloodshed of battle, of
jealousy, of mediating". Although the Brehon laws emphasize compensation over corporal punishment, the death penalty was a reality in Ireland. In the case of a homicide, for example, if the person refused to go before a Brehon or if he could not or would not pay the levied fine then he could lawfully be killed (Joyce, 1908). No Brehon would ever order physical punishments, as paying a fine was the standard legal punishment for any crime, but nonetheless punishments including death and blinding were common (Joyce, 1908). What this tells us is that while the Druids themselves did not advocate violence in criminal cases, it was socially acceptable for such punishments to occur. The Druids also advised kings, and this included advising military actions from cattle raids in Ireland to rebelling against Rome in Gaul; and we know as well from Tacitus's account of the destruction of Anglesey that the Druids stood against the opposing army. Juxtaposing that we also know that a Druid could stop a battle by walking between the two forces. Druids were expected to be wise enough to know when to encourage teh action and when to stop it.
In fact, rather than violence the main actions or traits that are condemned seem to be greed and lust. From the Triads of Ireland: "The three chief sins: avarice, gluttony, lust". A variety of the Brehon laws look at legislating states of marriage, sexual relations, and theft (I suggest reading Fergus Kelly's a Guide to Early Irish Law for more on this). According to Kelly's book theft could be punishable by hanging (Kelly, 1988). In some of the existing prophecies relating to the future or end of the world, such as the one given by Ferchetne in the Colloquy of Two Sages or the Morrigan's prophecy in the Cath Maige Tuired, a lot of emphasis is placed on the lack of honor, lack of modesty, false judgments, lack of truth, and a general going against the natural order of things that will occur. Similarly the Testament of Morann and the Instructions of King Cormac mac Airt emphasizes the importance of the king manifesting Truth, good judgment, generosity, and moderate behavior in order to uphold the bounty and prosperity of the land; this included being ambitious, invading neighbors, and punishing criminals. In Celtic thought there was clearly a link between correct ethics and behavior and the success or failure of life and the world itself, but those ethics, in general, seem to be directed at preserving the correct order of the world rather than improving it or idealizing it. People are not urged to abstain form alcohol or sex, or even violence, but to engage in those things in moderation and within the socially correct context; only when the actions exceed social acceptance or defy social order are there consequences.
So how do I relate this to other pagan ethics? I think Druidism in general is closer ethically to other recon faiths such as Asatru which emphasizes many of the same values. Although modern Druidry and Wicca share a common root in the friendship of Gardner and Nichols, a Druidism based more in the Celtic culture would seem to reject the modern Wiccan ethic of the Rede; although I believe there is a valid argument for the similarity in spirit of the original Rede and Drudic ethics. The original Rede, after all, was not an absolute moral law but a guideline for behavior that was open to personal choice with an understanding of consequences (I highly recommend Peter Coughlin's book Ethics and the Craft for more on this subject, or his online segments here http://www.waningmoon.com/ethics/rede.shtml). In the same way Celtic ethics appear to be based on the idea of personal responsibility and accepting the consequences of any action. However the modern Rede as it is understood by many people is seen as less flexible and more absolute and would be difficult to harmonize with my understanding of Celtic ethics. The Celts seemed to have an understanding of harm as having a place within the greater workings and balance of the world, and I have a difficult time envisioning a Druidic ethic that advocates the lack of balance inherent in a path that rejects all harm. People are expected to accept the consequences of their own actions, even if that consequence is harmful to them. The natural world is expected to endure some harm in support of human life. Even nature itself includes a balance between harm and life that is normative; natural forest fires destroy yet also clear the way for new growth, and life is often predicated on some level of harm to other living things.
How do I personally incorporate Celtic ethics into my practice of Druidism? I believe that the ultimate lessons of such ethics are Truth and moderation, and so this is what I seek in my life. Truth is an understanding of the nature of reality and of living in correct alignment with that reality; when I manifest Truth in my life then I also manifest positive qualities in the world around me. Another aspect of this is good judgment, since a person who is embracing Truth should consequently be able to correctly understand the nature of other things and reach correct judgments about them. Moderation is another key aspect, where a person should be generous without being careless, ambitious without being over-reaching, and brave without being foolish, for example. How does this relate to causing harm? Well, I see harm as sometimes necessary - there are times when a tree must be cut down for the good of the other trees, or for a need; there are times when a small pain is needed to prevent a greater one later. And there are times when violence is necessary as well. I know myself well enough to know that if my childrens' lives were threatened I would do whatever I had to in order to protect them, and knowing this I could never say that I live my life with the belief of never harming another person. I would be hypocritical to say such a thing. Although a great deal of my life is directed at preserving life and healing those who need healing, I know that sometimes we must defend ourselves. Sometimes we must bring harm, but I try to never do so without a reason. My ethic embraces harm only as it is absolutely necessary, creating a dynamic that nurtures life and healing but accepts the balance that nature requires. If I harvest a plant it is for food or another use; I have taught my children never to recklessly destroy plants for fun. When I eat meat I appreciate the sacrifice of the animal's life - truly when I eat anything I appreciate the living thing that died to feed me. And if I have to harm a person intentionally I see it as a last resort and do so only if it seems justified. This all applies equally to physical actions and to magic. I feel that this is most strongly in line with the ancient Celtic ethics and also is inline with the modern world.
To me the most important part is being able to understand if there is a need for the harm, and being able to accept the consequences of my own actions. If I cause harm then I try to follow the old Brehon law consequence of making reparations; I acknowledge what I did or my part in what happened and seek to recompense the involved or effected person. I strive to preserve harmony and balance within my understanding of Truth.
Joyce, P., (1908). a Smaller Social History of Ancient Ireland. Retrieved from http://www.alia.ie/tirnanog/sochis/sochis01.html#iv
Kelly, F., (1988). a Guide to Early Irish Law
Meyers, K., (1906) the Triads of Ireland. Retrieved from http://www.ucc.ie/celt/online/T103006.html