What good are Christian apologists and philosophers? I have argued elsewhere that we provide strength for our Christian brothers and sisters. However, many people, I suspect, are not too impressed by this. First, it may be a sense of piety, for them, to believe without any (or even in spite of the) evidence; perhaps, for some, the very idea of raising questions in this arena is untenable. But second, and perhaps more relevantly, many, perhaps even most, Christians, have very few questions, or do not significantly rely on intellectual argument. If that is the case, then what’s the overall practical benefit to Christian philosophy and apologetics? Where are the results in the grand scheme of things?
Setting aside the fact that the direct impact on believers is small numerically, but large qualitatively (and possibly indirectly large numerically), there is a definite benefit to evangelism. In what way? The Trinity functions as a good example. See, there are four main categories of objections to Christian belief (surely some objections cross categories, and some will quibble with them, but indulge me!). First, there are factual objections. These are objections that state that, as a matter of fact, Christianity doesn’t line up with the way the world is. Second, there are rationality objections. These are objections that say we don’t know (or perhaps can’t know) whether or not Christianity is true, but that Christians are acting irrationally by believing in God. Third, there are emotional objections that essentially state someone’s dislike of Christianity. Finally, there are logical objections. These objections deal with the logical coherency of Christian belief.
This is where the Trinity comes in. Out on the mission field, one encounters adherents of many other religions. These religious adherents, if exposed to the teachings of Christianity, find the doctrine of the Trinity extremely strange, if not logically contradictory. For them, it’s no more possible that the Trinity could be true than that 2+2=76! Many missionaries may be utterly stuck here, unable to advance more than the ideas that Christians ought to have faith, or whatnot. What a Christian philosopher/apologist can do is engage in evangelism on the front lines. She can defend the Trinity from objections such as the “1+1+1=3, not 1” objection.
This objection is that the Trinity is a form of polytheism (specifically, tritheism), and thus cannot be a monotheistic religion (a complaint often heard from Muslims). Especially with respect to Muslims, so long as this objection remains, they will not convert. The answer is to reply, “One what plus one what?” If they say “God,” then that just begs the question against Trinitarianism (e.g., Trinitarianism doesn’t claim, for example, that the Trinity is composed of three gods, so to present it this way is just to assume what one is trying to prove). If they say, “being,” we can again reply that the Trinitarian conception is “one God and three persons.” With that in play, we can now understand that Trinitarian theology agrees with “1+1+1=3, not 1,” by affirming that the things to be added are persons.
While Trinitarian discussions can go on and on, the point is that a simple objection that may throw the average missionary can be handled on the front lines of evangelism by the Christian philosopher/apologist (or at least by one who has training in these areas). If there are practical benefits to having Christian philosophers on the front lines of the Great Commission, then there are consequences to their total absence. I shudder to think at where we would be. In the future, if we do not have Christian philosophers involved in the Great Commission, the state of the church will be very poor indeed.
 To insist that this formula needs to be 1+1+1=1 with respect to persons, we’d really be endorsing a kind of modalism, where there is really only one person, so that there’s not really any math going on at all.