Google and Facebook are worth a combined $2 trillion, with the vast majority of their revenue coming from advertising. In our previous episode, we learned that TV advertising is much less effective than the industry says. Is digital any better? Some say yes, some say no — and some say we’re in a full-blown digital-ad bubble.

The modern world overwhelms us with sounds we didn’t ask for, like car alarms and cell-phone “halfalogues.” What does all this noise cost us in terms of productivity, health, and basic sanity?