Here’s an idiom that is sorely wanting in our modern day living and thinking: horse sense. Although there is some good news circulating here and there, it’s unfortunate that what seems to catch our attention are those things that show us at our lowest scale of being human.
In the 1830s, a horse reigned supreme. If you had any intention of getting from point A to point B in a relatively reasonable amount of time, a horse was part of the equation. Horses were a significant part of daily life back in those days. I believe they still are. Horses were as ubiquitous then as a car is today. The key–and important difference–is that a horse is a sentient creation, one that can feel, sense, experience and remember what goes on outside his/her physical body. Credit horse sense for those of us who’ve maintained a practical yet functional aspect of thinking reasonably.

A modern car is a marvel of technology, and that technology can deliver amazing conveniences in safety, comfort, even respond to inputs from the user [braking, turning, accelerating, navigation, e.g.] and of course, much more.

But unlike a horse, a car lacks the ability to feel and experience pain, joy, danger, fear, among other qualities of perception. Thus, being part of the animal kingdom, we are first and foremost, sentient beings. However, being human also means we are sapient creatures. We can reason, deduce and think about abstract concepts.
This is what makes us unique among all living things on this earth. We possess self-awareness, a conscious ability to think and reason to engage cognitive processes which in turn can further increase our understanding of things tangible and intangible.

We’re lacking a good amount of horse sense today. By any other name, it appears some have lost the basics of good judgement, fair decision-making, logical reasoning, even empathetic gestures and intentions.

“Well, it’s just pure, doggone horse sense______”
a) to wear a helmet when riding [horses, motorcycles, bikes, etc.]
b) to let go of that fire cracker once it’s @#!!# lit!
c) to wear that seatbelt regardless.
d) not to drive across that “shallow water” after a big rainstorm.
e) [and finally…] _____________________ [please, you think of something to add].
Here’s a comment attributed to French Enlightenment writer, philosopher and satirist, Voltaire [nom de plume; his legal name was Francois-Marie Arouet].
To wit: Common sense is not so common. I’ll bet he enjoyed horses.