systematicallymanipulate the independent variable to determine theeffect upon the dependent variable. Extraneous variables that may influence the outcome of theexperiment are rigorously controlled.
was one ofthe original founders of the humanistic perspective. His theories encompassedthe importance of unconditional and conditional positive regard in development of the 'selfconcept' and 'conditions of worth' set by others. His work has been applied to a rangeof domains, particularly in therapy through his development of'client-centred'(now class="d-title" named 'person-centred'therapy.