Shen Kuo was much in favor of philosophical Daoist notions which challenged the authority of empirical science in his day. Although much could be discerned through empirical observation and recorded study, Daoism asserted that the secrets of the universe were boundless, something that scientific investigation could merely express in fragments and partial understandings. Shen Kuo referred to the ancient Daoist "I Ching" in explaining the spiritual processes and attainment of foreknowledge that cannot be attained through "crude traces", which he likens to mathematical astronomy. Nathan Sivin proposes that Shen was the first in history to "make a clear distinction between our unconnected experiences and the unitary causal world we postulate to explain them," which Biderman and Scharfstein state is arguably inherent in the works of Heraclitus, Plato, and Democritus as well. Shen was a firm believer in destiny and prognostication, and made rational explanations for the relations between them. Shen held a special interest in fate, mystical divination, bizarre phenomena, yet warned against the tendency to believe that all matters in life were preordained. When describing an event where lightning had struck a house and all the wooden walls did not burn (but simply turned black) and lacquerwares inside were fine, yet metal objects had melted into liquid, Shen Kuo wrote: