A few hundred year ago the Europeans started using the lateen sail. The lateen sail could allow you to sail against the winds and therefore could leave port when you want.
The compass was a radical invention for navigators because it allowed sailors to sail at night and not have to rely on star charts. It was also critical for doubling the seasons of sailing – allowing you to sail in the overcast winter and not just the summer months.
With these inventions the Age of Exploration was possible, and world profits flooded into the European continent.
Fully 40% of the world's production rate is due to another such seasonal breakthrough, like the ones sailing had benefited from: air conditioning. As an author points out, without air conditioning:
“the deep-sea fishing industry would be deep-sixed; Michelangelo's frescoes in the Sistine Chapel would deteriorate; rare books and manuscripts would fall apart; deep mining for gold, silver and other metals would be impossible; the world's largest telescope wouldn't work; many of our children wouldn't be able to learn; and in Silicon Valley, the computer industry would crash.”
So give your respects to Willis Carrier, the inventor of modern air conditioning. The latter examples are how aircon got its start: besides reduced output due to overheated people, overheated machines were the major beneficiaries of Carrier. Our mechanical economy would break down without it.
Or you could just take the demon Azrael's approach: “No pleasure, no rapture, no exquisite sin greater... than central air.” Perhaps. But without it the fates of whole countries would still be tied to shorter working hours and siestas. Fair trade-off?