Damian was not tall and was very slender, not only because of his age but also due to his rigorous daily training. His exercise routine was more intense than that of many adult assassins, making it impossible for him to gain weight.
He stood in front of Deathstroke, looking up at his face, while the other looked at him kindly.
Suddenly, Su Ming hugged Damian, pressing his head against his own belly and gently stroked the back of Damian's head.
Da Mi quickly became alert and wanted to struggle, but Su Ming had already let him go.
"???"
What was going on? Why would the other party make such a gesture?
He looked suspiciously at the Otherworldly Deathstroke before him, but the other's helmet had already risen again, covering all expressions. The voice returned to a demonic whisper.
"Come on, I'll teach you how to solve a case." With that, Su Ming turned and left.
Damian touched the back of his head to ensure there was no bomb, but what was Deathstroke's intention? Something was off.
Despite thinking about this matter, he still emphasized, "Batman taught me."
Deathstroke turned back, his single red eye staring at him, exceptionally bright in the darkness: "He is him, I am me, our reasoning methods are different."
"Is that so?" Damian echoed, still pondering Deathstroke's abnormal behavior, that warm feeling seemingly still lingering on his head.
"I don't know if Batman ever taught you systematically, but how many types of reasoning methods are there?" Su Ming motioned for Damian's companions to come closer; the clues were right in front of them.
Damian rubbed his nose, feeling very uncomfortable: "Batman usually doesn't need too much reasoning because everything here is under surveillance."
"It's a pity that after the flood, all the surveillance equipment has been scrapped, he's going to have trouble this time."
Su Ming smiled, reinstalling all the cameras in Gotham, this wasn't just about wasting money, such covert things usually only he and Ah Fu dealt with, he wouldn't trust others with it.
Damian nodded, Batman wouldn't involve him in this matter, he would avoid letting other family members know his surveillance locations.
Su Ming didn't say more on this topic but instead spoke about the business at hand, explaining logical reasoning knowledge:
"There are generally five methods of logical reasoning, namely syllogism, conjunctive decomposition, chain deduction, comprehensive induction, and refutation by absurdity."
"Hmm..." Damian nodded, but others seemed somewhat distracted.
"Syllogism is a relatively well-known method, the most famous detective in the United Kingdom, Sherlock Holmes, is a proponent of logical syllogism. It emphasizes reasoning from two premises linked by a common concept to derive another property judgment as a conclusion."
Su Ming didn't care whether others listened or not; after all, this scene was for Damian, others could watch or not as they pleased. So he just watched Damian's face, waiting for his reaction.
Damian nodded, syllogism is a very stable and accurate method, using two premises to create a triangular clue chain, bringing together numerous clues to derive the truth.
This is a crime-solving method that requires very detailed observation, detectives using this method often have extraordinary observational skills.
Seeing him nod, looking serious, Su Ming smiled secretly but quickly became serious again and continued speaking.
"Many people use refutation by absurdity, arguing from the absurd conclusion of a proposition to demonstrate that it cannot be established, like cases of secret chamber murder, supernatural death, often you'd find more by backtracking from the result. This requires not only a brilliant mind but also a firm will, being convinced you thought of everything, it's a method of reasoning that completely restores the criminal method."
"Sounds a bit familiar, but it's not Batman's method." Damian said softly, holding his chin.
Su Ming also touched the chin area of his mask, nodding to Himeko, who was staring at him. She seemed interested, starting to pay attention.
"Batman is called the world's greatest detective, in fact, he just solves more cases. He is not good at refutation by absurdity, but someone was.... you probably don't know him, that person's name is Rorschach."
"Eliminate all possibilities, then whatever remains, no matter how improbable, must be the truth.... Right?" murmured Damian.
"Exactly." Su Ming confirmed with a nod, placing a hand on Da Mi's shoulder and continued: "The method Batman uses most is comprehensive induction, a reasoning method that derives a general conclusion from a large amount of individual knowledge, through piecing together related clues from a mass of irrelevant ones using common sense."
Da Mi seemed lost in thought, not caring about Su Ming's hand. He nodded: "Because he possesses a vast amount of information, along with supercomputers, it's a very effective method."
Su Ming continued: "In fact, Brother Eye itself can also reason, it uses conjunctive decomposition, for example, the probability of event A is 50%, and the probability of event B is also 50%, then when AB occur simultaneously, the possibility of causing a certain outcome is 25%, some people with strong brains can do this manually, though it's akin to computational decryption by brute force, finally finding the higher percentage among a heap of numbers."
"It seems the most scientific, yet in reality, it's the least accurate..." Damian took a deep breath, and Su Ming could feel his chest rise beneath his hand.
Su Ming nodded, with a hint of helplessness in his tone: "Yes, because it's a calculation, but it can't calculate an important variable, which is the human heart. People's behavior can be deduced from habits, but the thoughts in the human heart cannot be explained by mathematics."
Billy wiped his mouth, having just poured a large bottle of soda into it, and tossed the empty bottle out the door: "For example, sometimes I have a hamburger for breakfast, and sometimes a hot dog. Mathematically, the probability of choosing either is equal, but in my heart, I might actually want to have fried dough sticks and soy milk, which could make me suddenly change my habits. This variable is unpredictable."
"Exactly, and I bet you're lying; you don't even have a habit of eating breakfast." Su Ming shook his head slightly at him.
Fatty laughed again, scratching his head silly.
Of course, he's a hardcore homebody. Without tasks, he'd play computer games till late into the night, waking up the next afternoon. Why bother with breakfast?
"So, what is your method of deduction?" Damian brought the topic back, looking up at the person next to him. It was the first time he was this close to Deathstroke; he could even smell the blood on his armor.
Su Ming squatted halfway down, drawing a circle on the ground: "Since I'm not a detective, I don't have a strong desire for the truth. My method is the hopscotch jigsaw method."
"Wait, this doesn't seem to be one of the five methods you mentioned earlier." Wally, holding his head, crouched down too. Despite his fast thinking, he hated studying, so he didn't understand a thing.
To be honest, even Barry wouldn't be interested in this; otherwise, he would've become a detective instead of an evidence examiner.
"That's right, otherwise, how could I become the world's number one mercenary?"
From behind his mask, Su Ming's laughter rang out, as he lifted his hand from Damian's shoulder, making him feel a sudden emptiness as the weight was lifted.
Crush crossed her arms and turned her head aside: "Violent Wolf is the cosmos' number one bounty hunter. What's there to brag about being Earth's number one, tch~~~"
"True, but what connection does Violent Wolf have with you? Does he acknowledge you?" Su Ming sneered, suddenly appearing behind Crush, holding her head in his hand: "I'm bullying you today. Will he come after me for this?"
"You.... ugh!"
Though Crush had decent power, in strength and martial arts, she was still at a juvenile level and couldn't escape no matter how much she struggled.
"He wouldn't dare, because he's no match for me, hehe..."
Su Ming ruffled the young girl's hairstyle aggressively—a pretty little lady with tattoos, smoking, drinking, and following that Shamate style. She needed proper education.
Violent Wolf might be strong, but his biggest weakness was having zero magic resistance, easily countered by Su Ming in the DC universe. What was the Supreme Mage title for, just for fun?
"Don't touch her; if you want to pat heads, come for me!" Damian shouted quietly, his face expressionless, his thoughts unknown.
At Damian's words, Himeko glanced sideways at Da Mi and subtly shifted her feet, giving Da Mi a look of slight disdain, as if she'd discovered something.
But Su Ming didn't care about all that. He graciously flew back and placed his hand on Da Mi's head, patting it twice with satisfaction.
"Let's get to the point and stop teasing them." Damian's tone was filled with resignation, yet he made no attempt to free himself from the large hand.
"Alright, my method is more like playing jigsaw. First, clarify your purpose, then head towards it. It's more like starting from a center point, linking various different clues."
Su Ming looked at the corner of the room, where something seemed to have changed.
Damian blinked: "Isn't this the usual method corrupt cops use to frame people? Piecing together evidence chains."
"Naturally, it's different. If you only weave a single chain of clues, it certainly won't hold water; calling it framing wouldn't be wrong..."
Su Ming lightly brushed the back of his hand across his armor, as if wiping away nonexistent dust, and continued calmly.
"But if you can simultaneously construct hundreds of evidence chains and propose thousands of hypotheses, then regardless of whether it's conjecture or hypothesis, just eliminate the chains that don't fit common sense, are overly similar, or impossible to implement. Skillfully use the aforementioned five methods of deduction, link together the remaining indisputable points, and fill in the missing irrefutable evidence, and you'll find that the truth is right before you!"
"!!!"
Damian was first surprised, then wore a bitter expression; this wasn't something a normal human could accomplish. Even Brainiac might be needed for this kind of case-solving!
For the first time, Damian felt a bit of admiration for Otherworldly Deathstroke, as the latter seemed even better than Batman at solving cases...