Jan 2, 2019 · 20m · a16z
a16z Podcast | Bitcoin's Growing Pains -- and Possibilities
0:00 / 0:00
▶ Watch on YouTube →
gold bands on the timeline = statements, start to end. Hover to read, click to jump. CC turns on captions
In this episode of the a16z Podcast, host Michael Copeland and guest Chris Dixon speak with Bitcoin developer Mike Hearn to analyze the technical block size debate and the future of cryptocurrency scaling. They discuss practical decentralized applications like crowdfunding, strategies for consumer adoption, and Bitcoin's potential to drive global financial inclusion.
How this conversation actually went
Every chapter scored 0–10 on four independent dynamics. Hover any point for the reasoning behind the score. How this is scored →
The host as informed peer 6.5 Guest teaching 4.3 Guest disagreement 2.0 The host pushing back 3.0
speaking balance: gold is the host, purple is the guest (3 minute bins)
Sharpest disagreement ▶ 17:24 Mike Hearn counters Chris Dixon's disruption framing
Mike Hearn politely rejects Chris Dixon's premise that competing on merchant fee savings is ineffective, offering real-world European flight booking fees as counterevidence.
Hardest push from the host ▶ 3:56 Chris Dixon challenges anti-block-size limit perspectiveChris Dixon reframes the argument of anti-block-size proponents to forcefully highlight its paradox, characterizing it as preferring an unusable decentralized system over a working one.
Biggest teaching moment ▶ 2:22 Mike Hearn corrects Chris Dixon on Bitcoin maintainershipWhen Chris Dixon assumes Gavin Andresen is the current Bitcoin maintainer, Mike Hearn clarifies the succession from Satoshi to Gavin and then to Wladimir van der Laan.
The host holds their own ▶ 11:17 Chris Dixon elaborates on open protocols vs corporate platformsChris Dixon demonstrates deep venture expertise by articulating how open protocols foster free-market innovation, referencing historical precedents like SMTP and HTTP.
the scores for every segment, with the reasoning behind each
| Chapter | Topic | The host as informed peer | Guest teaching | Guest disagreement | The host pushing back | Why |
|---|---|---|---|---|---|---|
| The Bitcoin Block Size Debate Explained | 5 | 5 | 2 | 3 | Chris Dixon demonstrates moderate domain knowledge by asking targeted questions about the block size limit and off-chain scaling. Mike Hearn gently educates Dixon by correcting his assumption that Gavin Andresen is still the primary maintainer of Bitcoin Core. | |
| Decentralized Crowdfunding with Lighthouse and Bitcoin Scripting | 6 | 4 | 1 | 2 | Chris Dixon shows technical familiarity with Bitcoin's embedded scripting language and draws comparisons to Ethereum and Turing completeness security risks. Mike Hearn collaboratively explains the reverse-engineered origins of Bitcoin script and how Lighthouse utilizes it. | |
| Protocols vs. Centralized Platforms in Crowdfunding | 8 | 2 | 1 | 4 | Chris Dixon leads the conversation with a high-level thesis on open protocols versus corporate platform silos, drawing historical parallels to SMTP, HTTP, SSL, and VCRs. Mike Hearn concurs and offers the unbundling of services in Lightlist.io as concrete validation of Dixon's thesis. | |
| Strategies for Driving Consumer Bitcoin Adoption | 7 | 6 | 4 | 3 | Chris Dixon leverages Clay Christensen's disruption framework to argue that non-consumption use cases are more promising than merchant fee reduction. Mike Hearn respectfully challenges Dixon's framing, presenting practical European airline credit card surcharges as immediate proof that merchant fee reduction is already compelling. |
Statements from this episode (13)
Hearn: Satoshi set Bitcoin's 1MB limit when blocks were under 10KB
“He imposed a maximum one megabyte block size, and as there's one block every 10 minutes on average, that's, you know, you can calculate a maximum transaction rate from that. And at the time he put it in, we were around, you know, less than 10 kilobytes per blo…”
Hearn: Bitcoin will hit its 1MB block size limit next year
“And we're now at more like half of that block size, and it, you know, as traffic is growing, it looks like we might start hitting that limit sometime next year.”
Hearn: Satoshi named Gavin Andresen successor before Core maintainership passed to Wladimir van der Laan
“So when Satoshi left, he nominated Gavin Anderson as the, as his successor. And Gavin was maintainer of Bitcoin Core for a while, and then he delegated that again to Vladimir Vandalan.”
Hearn: Reaching Bitcoin capacity limits will kick users out of the system
“At worst, things break quite badly, but even at best, even if things don't break, some users won't be able to use Bitcoin, right? They will be kicked out of the system, effectively. There won't be enough capacity to handle them.”
Hearn: Lighthouse pledges stay under user control until target is met
“Lighthouse is a completely peer-to-peer and Decentralized approach. So you can actually pledge money to a project in such a way that it stays under your control until the moment that the project has raised the full amount.”
Hearn: Satoshi omitted Bitcoin's scripting language from white paper and emails
“For a long time, you know, for a long time it wasn't very well known, because Satoshi's white paper didn't mention it, and he didn't talk about it in, you know, his mailing list post either.”
Hearn: Developers have not fully utilized Bitcoin's scripting capabilities
“We've never really fully used the capabilities of even Bitcoin's fairly limited language.”
Dixon: Open protocols protect developers from being booted off by corporate platforms
“The great thing about open protocols is that they invite developers and entrepreneurs and investors To build on top of them in a way that they know they can do so safely and not sort of get booted off later the way that corporate controlled platforms tend to d…”
Hearn: Western Bitcoin adoption suffers from poor messaging, not lack of utility
“If you're in the West and you have access to, you know, credit card payments and so on, it's not always clear why you would want to use Bitcoin, but that's not because there aren't good reasons, it's because we're not doing a good job of, like, telling people …”
Hearn: Micro-tipping accelerates adoption by introducing users to spending Bitcoin
“Tipping has been really great for this as well, because, you know, people can receive a tip without even really expecting it, and then suddenly they feel like, hey, I've actually got some money, I could go down to a local cafe and buy myself a drink, and it's …”
Dixon: Bitcoin's greatest value is enabling new payment types
“I personally am much more excited about the latter kind for Bitcoin. In other words, I'm more excited about new ways that you can use Bitcoin and pay for things that you couldn't before. So for example, micro payments, machine to machine payments, versus save …”
Hearn: M-Pesa succeeded by bypassing Western anti-money laundering requirements
“M-Pesa was partly successful because it sort of ignored all of the Western anti-money laundering requirements and so on. Like you can just have a SIM card and start sending money, right, with M-Pesa in Kenya. You don't need to have a passport and, you know, an…”
Hearn: M-Pesa cannot support cross-border transactions, creating opportunity for Bitcoin
“The moment they want to trade across borders, systems like Impeza don't even work either. So there's a real niche, well, not even a niche, right? There's a real serious need for many people that Bitcoin can meet there.”