Is “Defensive Programming” actually healthy?

I can’t solve this one, and I think I need your help. So, a developer was responding to a code review comment I made and they simply asked me, “why would I do that?” I gave my standard, dusty answer: “because you have to code defensively— you don’t know what the future holds.” But I suddenly realized… am I proliferating a fear of the future? How could I code fearfully when I run CubicleBuddha.com where I blog so often about living happily in the present? I’ll share the specific code example with you. I’m hoping to hear from the community whether my solution is “coding in the moment” or if I am actually bowing down to the fear.

I’m sorry, but this “Full Stack” meme makes me really mad/sad

(This article was originally posted as a timed exclusive article for DEVCommunity. It resulted in an enormous number of responses. I feel privileged that I was able to start a transparent and honest conversation about the importance and misuse of job titles).

The meme above could potentially be casting shade on “full stack devs” by depicting them as a drawing of a horse but where only the backend is drawn out. If you were building a team, would you rather have that meme image above, or a developer who only knows one part of the system?