  The question of the sources of electric and magnetic fields and their causes
has been discussed extensively in the literature over the last decades. In this
article, we approach this problem from the unified treatment of electromagnetic
fields emphasizing the role of their sources in accordance with the
cause-effect relationships. First, we analyze whether this unified treatment
contributes to a better understanding of these phenomena. Then, we discuss the
implications for teaching of a correct understanding of electromagnetic field
sources and causality in Maxwell's equations. In particular, we present a
series of examples at the introductory physics level that allow us to recognize
the reasons why considering electric and magnetic fields as disjoint entities
can lead to contradictions.
