According to CG Jung, there are three levels of symbolism: personal, cultural, and universal.
Personal symbolism is what things mean to you. So, depending on what part of England you live in, the symbolic colour of earth might be different for you. If you live in Devon, where the soil is red, due to the red sandstone geology, then the symbolic colour of earth might be red for you; whereas if you live in the Cambridgeshire Fens, where earth is black, then you the symbolic colour of earth for you might be black. Personal symbolism may also vary depending on your experiences, your preferences, and your outlook on life. A particular tree might represent first love for you because you experienced your first kiss under it, for example. Or you might have a strong leaning towards the element of water, and therefore it might represent something particular for you.
Personal symbolic associations are not “wrong” or “incorrect” – but they don’t necessarily have any meaning for anyone else, unless they happen to share those associations. Poets and novelists often make use of personal symbolism to create new and interesting metaphors and imagery in their poems and stories.
Cultural symbolism is the set of symbolic associations something has within a particular culture. For example, in Europe, the colour black represents mourning; in other cultures, white is the colour of mourning. In China, the colour red is particularly lucky; in English folklore, a bride should never wear either red or green, because those are the colours of the Fair Folk. In China, dragons are associated with water, live in lakes and wells, and bring rain; in Europe, dragons are fiery creatures that live under the earth. And so on.
Universal symbolism is a symbolic association that appears to exist independently of culture, or that occurs in all cultures. Universal symbolism is generally derived from our perception of the world around us and how we relate to it. For example, a hearth-fire, being generally a pleasurable thing, is good and associated with hospitality; and cold/wet/dark/outside, being generally not pleasurable, is bad.When you are examining symbolism for use in ritual, it is a good idea to think about whether it is a personal symbol, only representing the thing symbolised for you and a small handful of others; a cultural symbol that is specific to a particular group of people; or a universal or very widespread symbol. It is of course fine to use a personal or cultural symbol in a ritual – but you may need to explain how you are using it, and what it means to you, or in the context of the culture or mythology you are drawing upon.
A related concept is that of Unverified Personal Gnosis (UPG) and Substantiated Personal Gnosis (SPG). An Unverified Personal Gnosis is an insight or revelation that you have received about the nature of a deity, or the nature of reality. It can be verified by checking it against experience, and/or other people’s insights and revelations, and/or with reference to the lore of the particular culture you are working within. The Unverified Personal Gnosis (UPG) is similar to personal symbolism – it is not “wrong”, but don’t expect other people to agree with you unless it chimes with their experience, or with the cultural lore associated with the deity and/or pantheon you are working with.
Many people are dismissive of UPG, but there is no need to dismiss it as “incorrect” – you only need to say that it doesn’t chime with your experience, and move on.
Many people are afraid that their personal symbolic associations with particular things are somehow wrong – but again, there is nothing wrong with creativity and personal symbolism, but your personal symbolism may not work for everyone. This is why magic and the occult are an art and not a science.