We’ve probably all made the error of mistaking hate for logic.

Of course, we didn’t realize it at the time. But that’s what we were doing.

Yesterday’s blog post got me thinking about the problem.

On my “Top 10” list of great people in history, I included the Byzantine Empress Theodora (497-548 CE). Most current historians think she was a remarkable woman. But in her own time, one writer had a burning hatred for her and her husband, Emperor Justinian.

That writer was Procopius, an aide to Justinian’s most important general, Belisarius.

It’s easy to guess why Procopius hated the imperial couple. General Belisarius had saved both them and their empire several times, but they treated him badly.

Misled by his own aides into suspecting Belisarius of disloyalty, Justinian often shorted him on troops and repeatedly sent him into nearly-impossible battles — all of which he won. Only Belisarius’s genuine loyalty to the emperor prevented him from seizing power when he could easily have done so. Procopius saw that. He blamed Theodora most of all, since she was born a commoner like Belisarius and should have been his defender.

About other aspects of the Byzantine Empire, historians consider Procopius a valuable source of information. George Ostrogorsky calls him “the outstanding historian of the age of Justinian.”

But anonymously, Procopius also wrote a book called The Secret History. In that book, warns Ostrogorsky, he acted as “a malicious pamphleteer” who tried to blacken the reputations of Theodora and Justinian. He devoted an entire chapter to “The Crimes of Theodora,” claiming for example that:

“Her animosity was ever ready to be aroused to the destruction of other people, and no power on earth could mitigate it.”

Let’s stipulate that running an empire is at times a brutal business. Mister Rogers would not be up to the task. Both Justinian and Theodora were up to it. As a result, the Byzantine Empire (the eastern half of the former Roman Empire) survived for 1,000 years after the fall of Rome. Justinian and Theodora were no worse than other imperial rulers, and they were better than most.

Why would a usually sane and reliable person like Procopius tell hateful lies about them? Well, he was human. Humans do that. Sometimes we mistake hate for logic.

Here are two arguments that look similar. The first is logically valid. The second is a rationalization for hate:

Hate is usually a waste of time and energy. It keeps us from seeing things clearly. It sometimes misleads us into committing wrongs that we later recognize and regret.

But in spite of all that, Argument 1 at least makes sense. It’s logically valid. If the premises (1 and 2) are true, then the conclusion (3) must be true.

Argument 2, on the other hand, doesn’t make sense.

If we hate someone, it proves nothing about that person. But it does motivate us to look for something — anything — that we can twist into “evidence” as justification for our hatred.

We believe that we’re good people — and most of us are, at least when we’re thinking straight. We like to believe that we wouldn’t hate someone without a good reason.

So we think that if we hate someone, there must be a good reason. We just need to find it. If we look and don’t find it, we need to keep looking. If we still can’t find it, we need to look some more. It must be there. It must be. Otherwise, we would be hating someone without reason. We’d feel embarrassed and ashamed.

Let’s not be too hard on ourselves. We’re not infallible. Our emotions sometimes cloud our judgment. That applies whether we’re smart or not; rich or not; good, bad, or indifferent.

But if we care about truth and doing the right thing, then we sometimes need to check our thinking.

Are we applying Argument 1 that makes sense? Or Argument 2 that rationalizes hate?

It makes a big difference. Be a thinker, not a hater.

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