The cryptocurrency community erupted in discussion on September 25, 2016, after former Bitcoin Core lead developer Gavin Andresen made striking comments about Ethereum’s growing decentralization — comments that reignited the long-running Bitcoin block size debate at a time when BTC was trading at approximately $600.
TL;DR
- Former Bitcoin Core lead Gavin Andresen tweeted that Ethereum’s lead as a decentralized network “will grow even as its blockchain size exceeds Bitcoin’s”
- Andresen clarified he wasn’t predicting Ethereum would replace Bitcoin, but arguing larger blockchains can stay decentralized
- Ethereum had approximately 6,000 nodes compared to Bitcoin’s 5,000 despite Bitcoin’s five-year head start
- The comments fueled the ongoing block size debate, with Andresen arguing against the 1MB limit
- Bitcoin traded at $600.83 while Ethereum sat at $13.10 on September 25, 2016
Andresen’s Provocative Tweet Sparks Interpretation Debate
On September 25, 2016, Gavin Andresen — who once served as the chief scientist of the Bitcoin Foundation and was an early contributor to Bitcoin Core — posted a tweet that sent ripples through the cryptocurrency community. He predicted that Ethereum’s lead as a blockchain network would continue to grow, even as its total blockchain size surpassed that of Bitcoin.
Many in the community interpreted Andresen’s statement as a bold prediction that Ethereum would eventually overtake Bitcoin as the world’s leading cryptocurrency. The price context added weight to the discussion: Bitcoin was trading at $600.83 with a market capitalization of $9.5 billion, while Ethereum was at $13.10 with a market cap of $1.1 billion, according to CoinMarketCap data from the same day.
Clarification: A Lesson in Blockchain Design, Not a Death Knell for Bitcoin
Speaking to Bitcoin.com, Andresen quickly clarified his position. He was not predicting the demise of Bitcoin or suggesting Ethereum would dethrone it. Instead, he was making a pointed argument about the relationship between blockchain size and decentralization — or rather, the lack of such a relationship.
“That doesn’t mean Bitcoin will be dead or that ether will replace bitcoin as the number one cryptocurrency,” Andresen stated. “5,000 nodes is plenty, it won’t matter much if Ethereum ends up with 100,000 — ordinary people don’t know or care how many nodes are relaying or validating their transactions.”
Andresen argued that even if the Bitcoin network shrank to 1,000 nodes spread across 50 countries, it would still be sufficiently decentralized. The real threats to the network, he suggested, existed at lower levels of the internet technology stack, such as the domain name system and border gateway protocol infrastructure.
The Block Size Debate Context
Andresen’s comments were deeply intertwined with the block size debate that was dividing the Bitcoin community throughout 2016. A major argument against increasing Bitcoin’s 1MB block size limit was that larger blocks would require more bandwidth and storage, potentially driving smaller node operators offline and centralizing the network.
Andresen had long opposed this reasoning. He pointed to Ethereum as living proof that a larger, more flexible blockchain protocol could maintain — and even grow — its node count. The fact that Ethereum had approximately 6,000 nodes compared to Bitcoin’s estimated 5,000 was, in his view, strong evidence that blockchain size and network centralization were not causally linked.
At the time, the Bitcoin blockchain was approximately 84.9 GB in size, while Ethereum’s was smaller but growing at a significantly faster rate. Some Ethereum client software also employed pruning techniques to reduce storage requirements, demonstrating that technical solutions could address scalability concerns without sacrificing decentralization.
A Divisive Figure in Bitcoin History
It’s worth noting that by September 2016, Andresen was no longer an active contributor to Bitcoin Core. Other Core developers had revoked his commit access earlier that year, largely due to his support for alternative Bitcoin implementations and his association with controversial figures. Despite this, his opinions continued to carry significant weight in the broader cryptocurrency community.
Andresen had previously pointed out that no other widely-used internet protocol imposed an arbitrary hard size limit comparable to Bitcoin’s 1MB block size cap. He maintained that current Bitcoin blocks were more full than many advocates realized, and that the network needed to address scaling concerns proactively.
Why This Matters
Andresen’s September 2016 comments were remarkably prescient. The block size debate would eventually lead to the Bitcoin Cash hard fork in August 2017, while Ethereum’s network would continue to grow both in node count and adoption. The question of whether larger blockchains can maintain decentralization remains central to crypto design philosophy today. Meanwhile, the notion that Bitcoin and Ethereum serve different purposes — rather than competing for the same crown — has become the consensus view. At $600 per BTC and $13 per ETH, both assets were still in the early chapters of their stories.
Disclaimer: This article is for informational purposes only and does not constitute financial advice. Past performance is not indicative of future results.