How monogamous are you in your variables?

“If you are an endocrinologist you are allowed to study a vast array of problems — sexuality, personality, growth, disease processes, etc. — in addition to the internal functioning of the endocrine system, so long as you explore the relationship between the endocrine system and those explananda. Endocrinology is monogamous in its explanatory variable — the hormone system — but promiscuous in its dependent variables. […] Oncology, in contrast, is a dependent variable discipline. As an oncologist you can study any conceivable cause of cancer — toxins, genetics, viruses, even psychological states. Oncology is monogamous in its dependent variable but promiscuous in its independent variables.”

—Erik Olin Wright, Class Counts