The theory was first published in 2005 a press released under the name of Cliff Arnall, who at the time was a tutor at the Centre for Lifelong Learning – a Further Education centre associated with Cardiff University. Later, however, the Guardian printed a statement from the university distancing itself from the psychology professor: University asked us to point out that Cliff Arnall... was a former part-time tutor at the university but left in February."Blue Monday, which falls on 18 January in 2016, is allegedly the most depressing day of the year.