"your philosophy of science" means what information you think is required before you will accept some causal claim as being true.
Consider a survey study that showed that people who drink 6 or more cups of tea a day have fewer health problems than people who don't drink tea.

A conservative philosophy of science would say no real causal statement can be made about tea causing health  since the study is not a true experiment. A true experiment is always needed to make causal statements.

A liberal philosophy of science would say if all plausible rival alternative hypotheses for the results have been evaluated and found to be relatively unimportant factors, for example dietary differences, exercise differences in the two groups, then you could conclude that tea causes health.     

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