I loved reading this! Frans de Waal is trying to make a point. We should be testing animals capabilities by designing these tests in ways that make sense for that specific animal. For example, one species of monkey would not use a tool other species could use. Finally they realized the monkey couldn't possibly use the tool because their hands are shaped differently. When they designed the tool to fit the physical needs of the monkey they used the tool as all the other species had. That is just one of many examples de Waal gives on how we've unfairly tested animal cognition. It was like a tour through the history of tests and observations of animals cognitive abilities, and how they have been debunked over time using methods like I mentioned. A very fascinating read!