~100 trillion synapses in human brain
Dave Blundin noted the human brain has roughly 100 billion neurons with 1,000 to 10,000 synapses per cell, yielding approximately 100 trillion synapses.
Snapshot · Moonshots with Peter Diamandis
Why AGI Is Close but Not Here Yet | Ray Kurzweil | EP #261
Explore episode
Jun 3, 2026
Where this was said
Why LLMs Went From Useless to Transformative in One Year
At 16:15 · chapter starts 14:30
Kurzweil explains the million-fold total computation increase and why LLMs only became effective recently. Dave Blundin and Kurzweil discuss brain synapses, parallelism, and why neural net parameters approximate biological synapses.
LLMs only effective for 6 months
Kurzweil argued that large language models have only been truly effective for the last six months, with models a year ago being largely unusable.
Human synapse: ~200 calcs/second
Kurzweil noted that individual synapses operate at roughly 200 calculations per second, but the brain achieves massive power through simultaneous parallel processing of all synapses.
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