  Two important aspects of Du Châtelet's broader philosophy are captured by this passage just quoted. The first is that she takes the natural world to be a whole whose parts are systematically interconnected. This natural systematicity is crucial to her scientific method, it sets her apart from many of her French Enlightenment peers, but there are nonetheless important limits to her willingness to call upon systematicity in her approach to investigations of the natural world.  We address these points in §5 and §6 below. The second important point implicit in the above-cited passage is that she clearly sides with what we would now call the intellectualist side of the voluntarist-intellectualist debate. Crudely, the debate centers around whether God's will or God's intellect takes precedence in his actions with respect to the created world, including the act of creation itself. A voluntarist would say that God's will takes precedence, and God could will anything to be the case. Whatever he wills just would be true and good because he willed it. Thus, God could have willed 2+2=5 to be true, and it would thereby be true. Conversely, an intellectualist would say that God's intellect takes precedence in his actions with respect to creation, including creation itself. He first understands what is true and good, and then he wills that certain things should attain because his intellect understands the truth and goodness of them (and his benevolence guides his choice). Earlier, Du Châtelet wavered on how to interpret the relation between God's will and intellect, but by the time she wrote the Foundations, she had clearly settled for the intellectualist side, and the PSR guides God in his choices no less than it guides humans. On this point, she is squarely in opposition to Voltaire who suggests that we should not search for, in his words, “sufficient causes” in nature for natural phenomena; rather we should bear in mind that the first cause of nature's activities is to be referred to God's will and  power.[8]  It is enough to appeal to this as the source of phenomena, and then leave it at that. Du Châtelet dissents from this approach, and not just because it mistakes, in her view, God's nature. Rather, it is an appeal we ought not to make as scientists (IP §162), for it is an utterly unscientific approach to a natural problem, putting the cause of the phenomena wholly beyond our ability to investigate   it.[9]  We return to this point in §5 below.