Whereas scientists principally use deduction
To all autodidacts: Imagine if YOU were to make a statement this absurd, without even a hint of self doubt. Worse, what if this is the kind of thing you actually believe as a result of your online "learning" adventures?
This is why a formal education is important. On your own, you could very well end up the the AC above -- so deeply misinformed that there's little hope for recovery.