Everyone has a worldview with either more or less ingrained foundational principles. Twentieth century theologian Carl F. H. Henry asserted that "Divine revelation [is] the basic epistemological axiom." That is, if God does not provide knowledge (and even the mind and ability to assimilate that knowledge), we can have no certainty about anything. Humanity's Creator has spoken to it what is good and right; sinners simply suppress that truth (Rom 1.18-32).
Before evaluating any issue, therefore, the question is: Is one's worldview—one's reasoning of everything—grounded in divine revelation, or in self-preservation and self-interest?
Simply telling someone who doesn't follow Jesus Christ that he or she is wrong and you disagree with his or her conclusions will usually only spark an unresolvable debate (not because the issue is unresolvable, but because the darkened anti-God, self-preserving mind will always ultimately reject holiness [Rom 8.7-8; Titus 1.15-16]).
So, the discussion might be better served if you simply communicate to your conversation partner that you realize the ground from which you derive your perspective seems to be at odds with what grounds his or hers, and that the worldviews from which you take your opposing stances are obviously fundamentally different. You can even tell your friend that you realize you probably won't reach a consensus because of that; but at least both of you will have the opportunity—whether or not that opportunity is seized with honesty—to examine your worldviews before the face of the thrice-holy God who would not have us grope around in darkness for how we should live.
Ultimately, there really are only two worldviews: Does the created order belong to God to do with as He pleases, and therefore we should endeavor at every level to direct our culture and our pleasures and/or approvals in accord with His revealed holy precepts for life? Or, as the masters of our own destinies, should we live as though the assertion of ancient Greek naturalist philosopher Protagoras is true, namely that, "Man is the measure of all things"?
In that worldview, no one should try to impose his or her views on anyone else because everyone is free and responsible enough to do whatever he or she wants, "so long as it doesn't harm me" (which, by the way, we all know is simply rationally and practically untenable).
Unfortunately, many of our individualistic 21st century peers naïvely assume that merely imagining we can live as such anthropological islands somehow magically trumps divine revelation's accurate portrait of the solidarity of Old Testament Israel [Deut 28-30; Josh 7], the New Testament church [1 Cor 12-14], communities in general [Matt 12.25-26; Eph 4; Phil 4.2-3], and even all humanity [Rom 5]). What one person advocates will inescapably affect the community, despite the denial of the naïve.
Where one locates himself on the scale of these two worldview poles will determine how he interacts with any issue, whether it be broader matters such as politics, economics, or environment, or more specific and personal concerns like work ethic, family construct, health care, organizational affiliation, etc.
Rather than unquestioningly allowing leadership to do the thinking for us, followers of Jesus Christ are charged by divine revelation to evaluate everything and hold fast to the good (1 Thess 5.21), to make righteous judgment (John 7.24), and not to be childish, but adults in their thinking (1 Cor 14.20). They are charged to be like King David, who learned that allowing divine revelation to ground his worldview equipped him with insight beyond all his enemies, teachers, and elders (Psa 119.98-100). In this way we, too, will be fully equipped to dialogue with the cursed and decaying culture around us and be the light that it so desperately needs.