<P> None of these connotations requires another, and they are not all equally inferred by uniformitarians . </P> <P> Gould explained Lyell's propositions in Time's Arrow, Time's Cycle (1987), stating that Lyell conflated two different types of propositions: a pair of methodological assumptions with a pair of substantive hypotheses . The four together make up Lyell's uniformitarianism . </P> <P> The two methodological assumptions below are accepted to be true by the majority of scientists and geologists . Gould claims that these philosophical propositions must be assumed before you can proceed as a scientist doing science . "You cannot go to a rocky outcrop and observe either the constancy of nature's laws or the working of unknown processes . It works the other way around ." You first assume these propositions and "then you go to the outcrop ." </P> <Dl> <Dd> <Ul> <Li> Uniformity of law across time and space: Natural laws are constant across space and time . </Li> </Ul> <Dl> <Dd> The axiom of uniformity of law is necessary in order for scientists to extrapolate (by inductive inference) into the unobservable past . The constancy of natural laws must be assumed in the study of the past; else we cannot meaningfully study it . </Dd> </Dl> </Dd> </Dl>

Who said the past causes the present and so the future