What is a Spell?

I guess this seems like an unusual topic, because many practicing witches think the answer is obvious, and yet so many disagree about what the answer is. This thread is to invite people to give me their personal opinions. My personal opinion is that a spell is a "suggestion to fate". The more powerful a spell is and the more experienced the witch, means a better and more successful suggestion. A successful spell in my opinion is a one with powerful symbolism. By sybolism I mean :
the properties of the ingredients used in spells,
The acitons carried out in the spell.
The way these things are used and done, and the reasons why.

An example of this would be the Japanese Tea Ceremony. Although this is more a tradition than a spell, it has the same qualities. Everything is done in a specific way and it is done in that way for a reason. Every action is symbolic of something. The actions done are the "language" of the ceremony. The power of suggestion .
A spell must speak the language of destiny, and this language is symbolism. A basic example of this would be the use of a rose in a love spell. The rose is a common symbol of love and therefore has become a common ingredient in such spells. A spell doesn't necessarily have to have specific ingredients, many things can be substituted or changed for anything which is symbolic of the same thing. However, Traditional spells are so commonly used because they are tried and tested. Replacing ingredients can be a dangerous business if someone overlooks certain factors. The replacement may have similar meanings and properties, but it is also unique and different. It has other qualities also which can totally change the "suggestion" and therefore the outcome of the spell. This has commonly led to unwanted side effects in many cases which I have personally experienced. I guess what I'm trying to say is that everything done in a spell must be deliberate and purposeful, because from the moment the spell begins, you are making that suggestion,......fate is listening. I'm very interested in hearing your opinions on this. I'm guessing that a topic such as this is something that anyone practicing the craft will have an opinion on. Anyone can pick up a spell bool and take an educated guess at why a certain ingredient is used in that kind of spell.

1) What is your definition of a spell?
2) Have you ever substituted ingredients or left ingredients out? What was the result?
All opinions welcome get posting!

Dear Celtic,

This reminds me of an university dissertation: thesis and anti-thesis... a science... in the Western world, a spritual tide arose as a anti-thesis of the science, however, even the way of this spiritual world: know the mechanism, casuality i.e. the cause and effect/result and these are the basic of the greek-european science! well in the Far East, we do think of the "pay-back" or "exchange" when we cast a spell, by which i mean there will always be a conswquence, for instance, you cast a spell, then it will be an effect but you will also receive a bit of mischievous pay-back, as if you are a small child and you jump in a small muddy pond for fun but you get mud on your cloth... Do you know what I mean by the Western witch-craft and spell casting is so scientific??? I will find my books of the Japanese warlock from 1000s and still very famous and worshipped (we never had a witch persecussion and so on in our history) and will try to quote more. Please do not misunderstand me. I do not mean to disregards the Western witch-craft. Au contraire, I am its student! With my greatest and sincere respect and regards, Anastasia