When you see someone claiming that SLS causes cancer, ask them where they found this information. Ask them what studies were conducted and how large the sample group might have been. Ask questions. Stay curious! If you don't understand, don't fear looking like an idiot for not knowing! We all start out not knowing things, but those of us who ask questions eventually learn as much as those teaching us!
And don't be proud of your lack of knowledge. I can't believe how many people wear the "I'm confused by science! (giggle)" badge with great pride. There is no shame in not knowing - no one is born knowing physics, although that would be a pretty cool thing indeed - but there should be shame in being proud of your ignorance. If you don't want to learn, don't learn. But don't make it cool to be uneducated.
I wasn't born knowing chemistry. In fact, up until about 5 years ago, I was English girl! I graduated with a degree in English and Canadian studies and was supposed to be a teacher of both fields. (They weren't hiring during the recession, so I became a social worker instead. That makes sense, eh?) I started making bath and body products and wanted to learn more. I upgraded my chemistry and math so I could understand more of what I was learning. I admit I have huge holes in my knowledge of all things science, but I strive to learn more every day. It's not an easy task, learning chemistry, but it's really fun!
“I mean, you could claim that anything's real if the only basis for believing in it is that nobody's proved it doesn't exist!” JK Rowling
Personal experiences are so important when making our products - we need to choose ingredients that offer us awesome skin feel, great cleansing, amazing moisturizing, and so on that suit our hair and skin type - but we need to make room for the science. When you say things like "I trust common sense more than science", you sound silly. (Which would you prefer the common sense remedies for TB from the pioneer days or modern medicine? And yes, I'm being extreme here.)
We need to know at least a little science to be good formulators. We need to know what is possible and what isn't. You can't violate the laws of physics and chemistry because you really want beeswax on its own to be an emulsifier. You shouldn't base your choices of ingredients on cutesy couplets or generalizations - for instance, anything with sodium in it is bad for you! And I ask that you learn why an ingredient is awesome rather than rely upon "this ingredient has been used for centuries by some group to treat their dry hair/foot fungus/desire for toasted bread" as your rationale for including an ingredient.
Stay curious. Ask questions. Be open. That's really all I can end with today...
click here to see the podcasts for The Infinite Monkey Cage radio show from the BBC (absolutely hilarious radio show about science, concentrating mostly on physics, but really easy to understand regardless of your knowledge level!) or click here for Dr. Joe Schwarcz's podcast, The Right Chemistry. It's three minutes long, but full of great stuff!
And check out this fantastic comic about science! That's going right beside my desk!
BTW: That element up there is my symbol. I like chemistry so much, I married a man named Nichols!