What does “lying is a delightful thing, for it leads to truth” mean in "Crime and Punishment"?

Question

From part II, chapter IV of Crime and Punishment by Fyodor Dostoevsky, translated by Constance Garnett:

Zossimov looked curiously at Raskolnikov. He did not stir.

“But I say, Razumihin, I wonder at you. What a busybody you are!” Zossimov observed.

“Maybe I am, but we will get him off anyway,” shouted Razumihin, bringing his fist down on the table. “What’s the most offensive is not their lying—one can always forgive lying—lying is a delightful thing, for it leads to truth—what is offensive is that they lie and worship their own lying.... I respect Porfiry, but... What threw them out at first? The door was locked, and when they came back with the porter it was open. So it followed that Koch and Pestryakov were the murderers—that was their logic!”

This says that lying leads to truth but I cannot see how.

Answer 1

This question Razumihin will answer himself (Part III, chapter I, same translation)

“What do you think?” shouted Razumihin, louder than ever, “you think I am attacking them for talking nonsense? Not a bit! I like them to talk nonsense. That’s man’s one privilege over all creation. Through error you come to the truth! I am a man because I err! You never reach any truth without making fourteen mistakes and very likely a hundred and fourteen. And a fine thing, too, in its way; but we can’t even make mistakes on our own account! Talk nonsense, but talk your own nonsense, and I’ll kiss you for it. To go wrong in one’s own way is better than to go right in someone else’s. In the first case you are a man, in the second you’re no better than a bird. Truth won’t escape you, but life can be cramped. There have been examples.

I don't know why, but the translator decided to use "to talk nonsense" and "to err" here for some reason, while in Russian text it is the same verb as in the quote in the question (врать).

The translation by Pevear and Volokhonskaya is much better:

“What do you think?” Razumikhin shouted, raising his voice even more. “You think it's because they're lying? Nonsense! I like it when people lie! Lying is man's only privilege over all other organisms. If you lie—you get to the truth! Lying is what makes me a man. Not one truth has ever been reached without first lying fourteen times or so, maybe a hundred and fourteen, and that's honorable in its way; well, but we can't even lie with our own minds! Lie to me, but in your own way, and I'll kiss you for it. Lying in one's own way is almost better than telling the truth in someone else's way; in the first case you're a man, and in the second—no better than a bird! The truth won't go away, but life can be nailed shut; there are examples.