To the Ancients, elementals were the physical explanation of the universe. However, some contemporary occultists see them only as symbols for forces and otherwise not 'real' at all. YIN YANG Chinese philosophy and acupuncture talk of yin yang. The list could go on. In Chinese literature it is quite long.
Some occultists suggest everything can be similarly arranged into related opposite pairs.
Here is a simple magical technique you may wish to try. List the four elements. Pete Carrol, Liber Null. Wing-Tsit Chan, A Source Book in Chinese Philosophy. Manly Hall, Unseen Forces.