The social and cultural zeitgeist is constantly evolving and each new generation prides themselves on being more progressive and liberal than the last.
This has probably been most evident in the evolution of sexual morals and proclivities and the shedding of sexual taboos from the prudish etiquette of the Victorian era to the free love movement and proliferation of the contraceptive pill in the 1960s.
In no other epoch has sex been so normalised and commoditised than it is now in the acceptance of the way people dress (or dress less), the narcissistic nature of social media and advertising in every facet of culture that plays on our primitive carnal senses.
Millennials, however, appear to be reversing the upward trend of sexual activity among generations, being the first of them to actually be having less sex than their parents did at the same age. Millennials, or Generation Y, are the generation which reached young adulthood around the year 2000.
A recent US Government study found that just 44 per cent of US teenage girls between the ages of 15-19 have had sex, compared with 58 per cent 25 years ago. There was a similar trend for boys surveyed, with 47 per cent having had sex, compared to 69 per cent among their parents when they were the same age. In percentage terms the decline is quite significant: 14 per cent among female and 22 per cent among male teenagers over the 1988-2013 period.
Dr Jean Twenge a psychologist from San Diego State University and author of the book Generation Me, which surveyed 11 million millennials in the US to examine its culture, found that millennials not only have less sex but have fewer sexual partners than their parents' generation at the same age. She also found that more than a third live with their parents well into their 20s.
Dubbed the "entitled generation", she posits that "after a childhood of optimism and high expectations, reality hit them like a smack in the face. That became even more true when the Great Recession hit in 2007."
There is a cocktail of unique circumstances that may have led to this intimacy disparity between the generations: the global financial crisis that struck when millennials were starting out in their working lives, longer working hours, less secure work and having to cohabit with relatives or flatmates due to soaring rents.
Dr Twenge, talking the Independent newspaper, said digital overload among tech-addicted millennials may be another contributing factor: "I suspect some of this is connected to the rise in digital communication, including online pornography. There have been cases in the media of some young men saying that pornography has made it difficult for them to have sex with a real woman."
Generation Me also expounds that millennials anger towards their Baby Boomer parents for the mess they have left for them may well be justified.
Paradoxically, Dr Twenge says: "This generation is more confident, assertive, entitled - and more miserable."