So, instead of trying to find the ideal type or the ideal average, he'd always look for the exception. So, in this example, which is an example of what's called Bateson's Rule, he has two kinds of mutations of a human thumb.
所以，与其寻找理想型 或是理想均值， 他总是寻找特例。所以，举例说， 在贝特森定律这个例子中， 他举出两种人类大拇指的突变基因。