Human values and the methods we employ for attaining them are continuous (w/neither epistemological nor ontological discontinuities, in other words, nondual). We can take Kant's interrogatories, for example, and map them such that our probes (methods) regarding 1) What can we know? = the descriptive = literal sense of scripture = awareness ; 2) What can we hope for? = evaluative = anagogical sense of scripture = hope; 3) What must we do? = normative = moral/prudential sense of scripture = love; 4) What does all of this mean? = interpretive = allegorical sense of scripture = faith. In other words, the hermeneutical spiral is essentially the same for the secular and the sacred. We could also ask how any given group of humans is dedicated, empowered, nurtured/healed and saved and map those enterprises, respectively, as the 1) cultural or theological 2) social or ecclesiological 3) economic or sacramental and 4) political or soteriological. Finally, we could map the 1) descriptive as science 2) evaluative as culture 3) normative as philosophy and 4) interpretive as religion.
This is to suggest, then, that a person with a pneumatological imagination, in other words, who sees the Spirit at work always, everywhere and in everyone, the secular will represent the Spirit at work, implicitly, in the descriptive, evaluative, normative and interpretive, in science, culture, philosophy and in all religions (although, from place to place and time to time, human cooperation with the Spirit and the values thus realized - or frustrated - may vary in degree for manifold reasons). Any explicit recognition of Spirit will amplify the epistemic risks already undertaken (in epistemic virtue) through an interpretive lens that engages awareness, hope, love & faith (a/theological virtue) toward the end of augmenting the values of truth, beauty, goodness and unity.
Bottomline, Sagan realized the same values and employed, essentially, the same methods any believer does. Believers would claim that they take more epistemic risks (though not without epistemic virtue) than Sagan did with an aim toward augmenting the values they might then realize. Perhaps many have but that would have to be measured sociologically in terms of intellectual, affective, moral, sociopolitical and religious growth (Lonergan's conversions), which is more than a tad problematic. Many clearly have not, though, and that's easy to see with simple common sense.