In the early 2010s, an experiment asked 21 four-year-old children to look at a screen and select one of two boxes displayed — whichever they thought contained the fewest dots. Three-quarters of them chose correctly when both boxes contained one or more dots. But when a box with zero dots was added as an option, that proportion fell to below 50 per cent. Whether it’s because learning to count often starts with “one”, or because it is associated with the presence (rather than absence) of real-world objects, the idea of nothingness as a number just didn’t compute as intuitively.
在2010年代初，一项实验要求21名四岁的孩子看着屏幕，从屏幕上显示的两个盒子中选择一个——他们认为包含的点最少的那个。当两个盒子都包含一个或多个点时，四分之三的人选择正确。但当一个没有点的盒子作为选项时，这一比例降至50%以下。不知是因为学习数数通常从“1”开始，还是因为它与现实世界中物体的存在(而不是不存在)有关，“无”作为数字的概念并没有那么直观地计算出来。