Submitted by Pia van der Velde (

Citation Note

Address delivered at the occasion of accepting the appointment as Endowed Professor of Consumer Behavior and Marketing, on behalf of the Erasmus Trustfonds, Erasmus University Rotterdam, at the Rotterdam School of Management, Erasmus University Rotterdam on Friday 18 May 2018


For more than a century, scholars in psychology have debated whether humans are ‘of

two minds,’ that is, whether they have both conscious and unconscious thoughts, and

whether both conscious and unconscious thought processes determine their behavior.

According to Freud’s iceberg model, conscious thought is just the tip of the iceberg,

with most of our thought processes taking place unconsciously. Marketing scholars and

practitioners have embraced the iceberg model with great enthusiasm. They have

incorporated models where people’s drives and motivations are built in layers, with only

the top layer consciously accessible, but the real drivers hidden underneath. According

to one of the most influential contemporary theories, human thinking is governed by

dual systems. System 1, it is argued, is the evolutionarily oldest system, based in parts of

the brain we share with lower animals, operates unconsciously, uncontrollably, with low

effort, has huge capacity, is fast, nonverbal, parallel, and associative. System 2,

conversely, is evolutionarily more recent, resides in our frontal cortex, operates

consciously, controllably, with high effort, has small capacity, is slow, verbal, serial, and

based on rules.

Despite their intuitive appeal, dual system theories have been challenged in recent

years. I discuss some of their more problematic aspects and the research I have

conducted testing core propositions of the dual system approach. Especially my

research on the way brands become more well-liked through advertising and

conditioning procedures is highly relevant for the debate, but so is research on people’s

risk perceptions and self-control performance. Overall, I have seen support for some of

the key predictions of dual process theory, but no support at all for its strong claim that

mental processes should clearly belong to one of two systems with highly separable

features. I argue that we need to acknowledge that the human mind cannot be neatly

divided into two complementary processing systems. Rather, we should recognize that

thought processes can be characterized to a greater or lesser extent by some but not

all the features of automaticity. Researchers should start recognizing the full complexity

of the human mind and embrace research that is more detailed, more precise – and

perhaps a bit less grand in its claims.

Inaugural Lecture