Use your intuition and logic, too. I can't say it is a combo of tradition/instincts because if I relied on my parents way of parenting me I wouldn't get too far. I use common sense coupled with my intuition. Of course, you need to be on a lookout for what's new, too. You need to know that certain plastics, for example, were recently found to be risky for use with babies (and humans in general) so this is something you need to take into consideration. Although advances in science make our life more convenient, we need to apply our common sense and think if a new gadget won't be proven in 5 years to have some adverse effects on babies' health and safety.