Natural Philosophy is a term which has various definitions. During the enlightenment era, the natural philosophy was a form of monism, espoused by men such as Joseph Priestly, which sought to purify Christianity of distortions that could not be substantiated by observation or reason so that in cooperation with science it could withstand superstition and political oppression. Against this view, the skeptical agnosticism of David Hume posed the greatest threat.
Hume’s central premise was that it was impossible to obtain knowledge of God through observation of the natural world. The virtuous purists of humanity; justice morality politics and religion were conditioned by culture not reason. Hume emphasized the limitations of the analogical logic which undergirded the teleological argument from natural theologians on the basis that an infinite God needs not be extrapolated as the necessary cause of the finite mechanistic creation. The limits of inductive logic meant, according to Hume, that while God might be possible, there was no empirical test to validate Him as the supernatural causal force. The greater the claim, the greater the evidence one must have to establish it and not such extraordinary evidence can be construed from science. Additionally, since our cosmos is a singularity unverifiable by observation of multiple worlds, there was no way to conclude it is a result of design. The illusion of design is a failed attempt to explain natural adaptation and which fails to account for suffering.
The strength of Hume’s thought was recognizing the limitations of the mechanistic analogs favored by natural theologians which were in no way superior to the older organic analogies. Hume’s rejection of the Deistic transcendent God unintentionally opened the door for God’s imminent work in creation. However, Hume’s skepticism fails on three grounds. First, his assumption that extraordinary claims require extraordinary evidence is itself a non-scientific assertion. Nothing in experimental science reinforces this claim that singularities require extra evidence. The claim itself becomes unique and extraordinary but lacks any extraordinary evidence. Thus, Hume’s first premise becomes self-refuting and invalid. Second, his claim that science disproves a supernatural cause for nature is flawed in that he assumes the conclusion in the premise. Hume’s argument is rooted in the assumption that miracles cannot occur and therefore no evidence of miracles can be found. Finally, Hume’s threshold for validating the teleological argument is absolute certainty, but this is not the test for any scientific truth. The philosophic and scientific threshold is one of high probability, not absolutism.
 John Hedley Brooke, Science and Religion: Some Historical Perspectives, Canto classics edition. ed., Canto classics (United Kingdom: Cambridge University Press, 2014), 240.
 Ibid., 246.