Eclecticism

Eclecticism is a conceptual approach that does not hold rigidly to a single paradigm or set of assumptions, but instead draws upon multiple theories, styles, or ideas to gain complementary insights into a subject, or applies different theories in particular cases. It can be inelegant, and eclectics are sometimes criticised for lack of consistency in their thinking, but it is common in many fields of study. For example, most psychologists accept parts of behaviorism, but do not attempt to use the theory to explain all aspects of human behavior. A statistician may use frequentist techniques on one occasion and Bayesian ones on another. An example of eclecticism in economics is John Dunning's eclectic theory of international production.

Origin
Eclecticism was first practiced by a group of ancient philosophers who attached themselves to no real system, but selected from existing philosophical beliefs those doctrines that seemed most reasonable to them. Out of this collected material they constructed their new system of philosophy. The term comes from the Greek eklektikos: choosing the best. Well known eclectics in Greek philosophy were the Stoics Panaetius and Posidonius, and the New Academics Carneades and Philo of Larissa. Among the Romans, Cicero was thoroughly eclectic, as he united the Peripatetic, Stoic, and New Academic doctrines. Further eclectics were Varro and Seneca.

Psychology
Eclecticism is recognized in approaches to psychology that see many factors influencing behaviour and the psyche, and among those who consider all perspectives in identifying, changing, explaining, and determining behaviour.