Berkouwer's leadership within the denomination to which most of them belonged was strengthened by this openness of the leading GKN theologian, and it contributed to Berkouwer's developing in turn his own position in tandem with that of his friend Berkhof. In an end-of-career work published in English but not Dutch, "Two Hundred Years of Theology: A Report of a Personal Journey" (Grand Rapids, Michigan: Eerdmans, 1989), Berkhof assessed – along with many other philosophers, philosophical theologians, and systematic theologians – a few leading Gereformeerde historical figures, including Abraham Kuyper and Berkouwer. Berkhof said of the latter, who was in his "Studies" so leery of speculation, that he suffered from being "not speculative enough." But he added that since Berkouwer wanted to produce work in systematic theology that was grounded in careful exegesis of the biblical texts for all doctrinal teaching, according to a Reformed tradition of interpretation of the Bible, he mentions few philosophers and interacts sparingly with only one contemporary philosopher, Dooyeweerd, who theologically seems to have had some kinship with Berkouwer and Berkhof's Middle Orthodoxy.