When it comes to societal norms always question "why is this so? Does it truly benefit me? Is there an unsaid party that also benefits or may benefit at my expense?" (Things such as consumer culture, dating rituals [proposing on one knee for marriage or paying for a date], or healthcare system practices).
I.e. Do I really need the next I-Phone upgrade? --> Why is there an upgrade every time I turn around? --> Do I really benefit from said upgrade or is their a party that benefits more than me at my expense? --> Conclusion = As long as I can still call/text/browse I don't need an upgrade and chances are high that Apple purposefully puts out upgrades regularly to sell more products. Therefore I'm not going to buy an upgrade until my phone is broken.
I.e. Dating Rituals - Paying for dates --> Why are guys expected to pay for dates? --> Does paying for the date increase or decrease my chances of success with this girl (does it benefit ME)? --> Conclusion = In the early 1900's women didn't have enough residual income to go out on the town and NEEDED a man to pay their way in order to go out and have fun. The man NEEDED to pay in order to be accompanied by a woman. Today women have way more than enough residual income to pay for themselves and after having tested both paying and going dutch I have concluded I get laid more when I do NOT pay for the womans date.
I.e. Healthcare System Practices - Your Doctor Prescribes You Take An Anti-Depressant for Depression --> What causes depression in the first place? --> Is a powerful chemical really the best way to eradicate depression in the first place? Are there alternatives? --> Why is powerful chemical medication the first plan of action as opposed to a last resort? --> Does an unnamed party benefit at my expense?
--> Conclusion: Depression is caused by a number of psychological, environmental, and physiological factors including nutrient deficiency's, stress/social isolation, hereditary mental illnesses, and even a disrupted intestinal microbiome. I need to figure out which of these factors is the true cause of my depression and then take action to fix it before resorting to a powerful brain altering chemical. Pharmaceutical companies profit greatly from prescribing medication and most mainstream doctors aren't trained to look into root causes of chronic illnesses to try and first solve the problem without chemical intervention.
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Basically a big aspect of critical thinking is just questioning the status quo of what society tells you is "right" or "the way things are". The hard part is identifying those status quo issues that you subscribe to as most of the time we aren't even aware we're doing them since its just "the way things are".
Unfortunately for issues of these nature a big aspect of critical thinking involves field testing and research. But for the issues that are truly important to your life its inherent to come to a well informed consensus on matters that directly impact your well being.
-Rob