He applied the “Page 99 Test” to his new book, Trusting What You're Told: How Children Learn from Others, and reported the following:
If you open my book Trusting What You're Told you'll get a glimpse of some of the experimental questions that are tackled in the book. In particular, you'll learn how preschoolers don't listen to, and learn from, just anyone - they are sensitive to the fact that some claims are made by several people whereas some are made by a single person and they typically agree with the consensus. This is one illustration of a more general theme in the book: children are not indiscriminately credulous - they tend to accept information from some sources over others. Nevertheless, the book also underlines that children depend in a very deep way on what other people say in order to learn about the world. For example, children cannot observe the historical past for themselves - they learn about history from what other people tell them. Similarly, they cannot conduct scientific experiments for themselves - they learn that the mind depends on the brain, that the world is round, that man evolved from other species, or that the climate is changing - by listening to what other people tell them. Children also turn to others, and trust what other people say, when acquiring religious beliefs, whether concerning the power of prayer, the nature of God, or the possibility of an afterlife.Learn more about Trusting What You're Told at the Harvard University Press website.
One common metaphor for thinking about early cognitive development is to think of the child as a little scientist, who gathers data and builds up theories and concepts on the basis of personal observation. However, this book argues that there are various domains in which this metaphor is inapplicable - children cannot gather the relevant data for themselves and so they end up trusting what other people tell them.