The Two Types of Fool

Casey Ellis, founder of Bugcrowd, opens with a reflection built over the past year. He introduces the talk's central idea, drawn from a book: there are two kinds of fool, one who assumes the old is automatically good and one who assumes the new is automatically better. Neither is entirely right. He illustrates the middle ground with former early bounty hunters who now run their own companies, building on what they were taught while bringing fresh approaches.

The middle section argues that knowledge sharing across generations is urgent. Ellis points out that older technology still underpins the internet, that hybrid conflict and fast deployment outpace defenders, and that cheap attack tools lower the bar for disruption. He covers humility and knowing one's strengths, balancing curiosity with ego, and gratitude as a force multiplier that still allows people to push for change. He also describes mentoring, public-good work and the value of community in policy and entrepreneurship.

He closes by addressing three groups: younger practitioners, who bring essential skills and will inherit today's problems; middle-career people, who connect others; and senior practitioners, who should stay engaged and listen rather than dictate. He ends with a personal warning about burnout after a serious heart condition, urging people to check on peers who are overworking.