This question needs quite a bit of unpacking. For a start, one must distinguish between truth and evidence. To a realist, something may be true without there being any evidence for it. I have no evidence as to whether it rained on Lands End in England at noon on May 1st of the year 1 CE, and I strongly suspect that no such evidence exists or will ever come to light. But I believe that proposition is either true or its negation is true. I have no evidence as to whether matter existed prior to the big bang, but I'm willing to believe that either it did, or it didn't.
This means that the primitive idea that only verifiable sentences are meaningful is simply false. Furthermore, sentences, and even whole theories, typically are not verifiable at all, but only falsifiable. Even if we accept a kind of inductive reasoning, such as that of bayesianism, we cannot speak of verifying hypotheses or theories in any absolute sense, but only in comparison to rival hypotheses. If I have two rival hypotheses A and B, and A gives a better account of the data than B, then I'm willing to say that A is confirmed relative to B, but I cannot rule out that an even better hypothesis C might come along in future and trump both of them.
I suspect that despite your question being framed in terms of truth, what matters more to you is whether one has evidence for a belief. This question might be phrased, should one believe anything without some evidence? Even this is a highly contentious claim. To begin with, you have to address Agrippa's Trilemma. The only thing that can provide evidence for a belief is apparently another belief, so where does evidence come from? Any evidential claim must either (1) be circular, (2) involve a regress, or (3) involve an appeal to a belief that is infallibly and indubitably true. None of these options is very appealing.
Even if you think you can surmount this hurdle, one must address conventionalist objections that what counts as evidence depends on all kinds of methodological and linguistic assumptions. So you and your opponent may be working with different criteria of what counts as evidence with respect to some domain. What counts as evidence of the existence of God, for example? (Wittgenstein, and the later Carnap, regarded theological language as a distinct language game with its own rules that allowed assertions to be made that didn't admit of falsification in the usual way.)
And even if, in straightforward scientific cases, all this can be resolved satisfactorily, does it generalise to other kinds of judgement, e.g. moral or aesthetic judgements? Is it true that one ought to do unto others as you would have them to do to you? Is it true that Adolf Hitler was a bad man and Albert Schweitzer was a good man? Is it true that wisdom is a virtue and greed is a vice? Is it true that Bach's music is beautiful and my tuneless whistling is not? One might reasonably have firm beliefs about any of these without being able to explain how it is supported by logic or empirical data.