Today's Wisdom - Coffee, Comedy, and Climate

Welcome back to the 'A Little Wiser' newsletter.

Rarely do we get to hear from someone who has navigated both the highest halls of government and the world’s most urgent humanitarian crises. This is a special feature lesson you won’t want to miss. Onto today’s wisdom:

Let’s dive in.

Caffeine is the most widely consumed psychoactive substance on Earth, and unlike most of its chemical cousins, it enjoys a surprisingly good reputation in science. Large-scale observational studies consistently show that moderate caffeine consumption is associated with lower all-cause mortality. A landmark 2018 study in JAMA Internal Medicine following nearly half a million people found that coffee drinkers had a reduced risk of death from heart disease, stroke, diabetes, and neurological conditions. Caffeine works primarily by blocking adenosine, the molecule that signals fatigue in the brain, but its benefits extend far beyond alertness.

The brain seems to be one of its biggest beneficiaries. Multiple long-term studies have linked regular caffeine intake to a lower risk of neurodegenerative diseases like Parkinson’s and Alzheimer’s. In Parkinson’s disease, caffeine appears to protect dopamine-producing neurons, a rare example of a common dietary compound influencing a serious neurological pathway. Short-term effects are just as well documented: randomized controlled trials show caffeine improves reaction time, focus, and endurance, which is why it’s one of the most studied performance enhancers in sports science. Interestingly, caffeine also enhances fat oxidation during exercise, helping explain why it improves endurance rather than just making you feel awake.

But caffeine is a classic case of “the dose makes the poison.” Beyond about 400 mg per day (roughly four strong cups of coffee), the benefits flatten and risks rise. Excess intake is linked to anxiety, sleep disruption, elevated heart rates, and in some people, increased blood pressure. Genetics matter here: studies show that people with slower caffeine metabolism experience more negative cardiovascular effects at high doses. Timing matters too. Research from sleep labs demonstrates that caffeine consumed even six hours before bedtime can reduce total sleep time and quality, quietly undermining health gains elsewhere. The verdict from modern science is nuanced but clear. Caffeine is neither a miracle nor a menace. Used intentionally (timed earlier in the day, consumed in moderation, and tailored to individual sensitivity) it can be a powerful cognitive tool. Used mindlessly, it becomes a loan taken against tomorrow’s energy, with interest charged at night.

Voltaire lived in an age when disagreeing with the wrong person could land you in prison, exile, or worse. Born François-Marie Arouet in 1694, he learned early that ideas were dangerous things. After mocking a powerful nobleman, he was beaten and thrown into the Bastille, an experience that permanently shaped his worldview. Voltaire emerged convinced that direct confrontation with authority was often suicidal. Satire, he realized, could slip past censors, embarrass tyrants, and expose absurdities without waving a flag of rebellion. In an era of absolute monarchs and unquestioned religious authority, laughter became his sharpest weapon.

On November 1, 1755, an earthquake struck Lisbon, killing between 30,000 and 60,000 people. The disaster fractured the philosophical foundation of the Enlightenment. For decades, Leibniz had argued this was "the best of all possible worlds," where even apparent evils served a greater good. Voltaire, then 61 and living in exile, saw proof that the world was governed by chaos, not providence. In December 1755, he composed a savage poem attacking optimism. Four years later, he published his answer simultaneously in five cities to outrun censors: Candide.

The book sold 20,000 copies in its first year despite being condemned by the Geneva city council and banned by The Vatican. The plot follows Candide, a naive young man tutored by Professor Pangloss, who insists "all is for the best" even as Candide experiences war, rape, earthquakes, and slavery. Pangloss is hanged, enslaved, and maimed, yet refuses to recant because "I am a philosopher." The novel ends with Candide rejecting grand theories insisting that "we must cultivate our garden" instead. The power of Candide lies in what it ridicules, not what it argues. You can refute an argument, but you cannot un-laugh at a joke. Voltaire attacked religion, monarchy, and colonialism by wrapping radical ideas in adventure. Today, political cartoons, late-night comedy, and satirical journalism all trace a lineage back to Voltaire’s insight. In a world still crowded with certainty and authority, satire remains one of the most effective tools for reminding power that it is not sacred.

Below - a free PDF of Voltaire’s most celebrated work Candide, enjoy!

The greenhouse effect starts with a simple balance of energy: our planet absorbs heat from the Sun, but it must also release it back into space. Sunlight passes through the atmosphere and warms the planet’s surface, which then releases that energy back upward as infrared radiation. Certain gases in the atmosphere, mainly carbon dioxide, methane, and water vapor, trap some of this outgoing heat and reflect it back toward the surface. Without this process, Earth would be a frozen rock, about 33°C colder on average, incapable of supporting life as we know it. In that sense, the greenhouse effect is not a problem at all; it’s a prerequisite for civilization.

The problem arises because humans have been intensifying this natural system. Since the Industrial Revolution, burning coal, oil, and gas has rapidly increased the concentration of greenhouse gases, especially carbon dioxide. Before industrialization, atmospheric CO₂ hovered around 280 parts per million. Today it exceeds a level of 420 which we have not seen for millions of years. These gases don’t just trap heat briefly; CO₂ lingers in the atmosphere for centuries. This means today’s emissions commit the planet to long-term warming, even if emissions were reduced tomorrow. The climate system responds slowly but relentlessly, like a giant heat reservoir that takes decades to cool.

The effects of this extra trapped heat are already reshaping the planet. Warmer oceans expand and raise sea levels. Heat disrupts weather patterns, intensifying droughts, floods, and storms rather than simply making everywhere “hotter.” Ice sheets melt not just from warm air, but from warming seas undermining them from below. What makes the greenhouse effect so consequential is its invisibility: there is no single dramatic moment, no switch flipped. Instead, small annual changes accumulate into irreversible shifts. Understanding the greenhouse effect is about grasping how a thin layer of gases, altered by human activity, now governs the future stability of the only climate we’ve ever known.

Below - This graph tracks the global temperature anomaly from 1850 to 2024, showing how much the Earth’s average temperature has deviated from the 1850–1900 baseline.

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Until next time…. - A Little Wiser Team

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