By every definition of the word, Thanos was insane. But now, based on what we saw in Avengers: Endgame, we can assume that the pragmatic warlord was a hypocrite as well.
The Mad Titan, in his crusade to save the universe from overpopulation, always claimed that he killed people randomly and dispassionately. So, when he got his hands on all six Infinity Stones in Avengers: Infinity War, people assumed Thanos objectively went through with his plan and wiped out half of all living creatures in the universe, which makes no logical sense when you think about it. But to explore whether Thanos’ rampage was really indiscriminate, we have to take a look at his family and backstory.
When Thanos and Gamora visit Red Skull on Vormir, the former leader of HYDRA recognized the Mad Titan as “Thanos, son of Eros.” However, Eros is actually Thanos’ brother in the comics. Their father, A’lars aka Mentor, is a benevolent god-like scientist belonging to the race of Eternals. As you’d expect, though, we can’t exactly say the same about his son.
In fact, Thanos was malicious. He repeatedly attacked Titan and even killed his own mother. And when he got his hands on the Infinity Stones, he made sure that Mentor was among the dead when he snapped his fingers to wipe out half the universe, later explaining to Eros that he didn’t want their father to stand in his way.
Of course, the MCU portrayed Thanos as a rational martyr, but was he as indiscriminate as he claimed? If the Snap left a fifty-fifty chance of surviving, then how did the Mad Titan ensure his survival? I mean, if he was dusted alongside everyone else, that would leave the stones for someone as powerful as Thor to pick them up and reverse everything, the same way the Avengers did in the last movie.
Besides, Doctor Strange saw millions of possible futures in Infinity War, so why did he say that the Avengers only won in one of them? Because if we’re giving Thanos the luxury of chance, he couldn’t possibly have survived in all of the alternate dimensions, right? If the Mad Titan was really indiscriminate, he would’ve perished and failed in millions of realities.
Then again, this would’ve denied us the fun of Avengers: Endgame, so we can’t really complain about the integrity of Thanos’ moral code when it came to purging half of all living things in existence. But it seems that the Mad Titan made sure to spare himself when he performed the Snap, meaning he was able to choose which half of the universe was left alive.