<p>It is never “completely safe” to post anything online. Remember the Law of Unintended Consequences and there are always unforeseen consequences.</p>
<p>But there’s one that’s foreseeable even if not likely - Suppose a prospective employer finds that essay say, 20 years down the road, and judges your writing ability at least partly on the basis of that essay. I know that when I was 18, I thought my essays were works of art/literature/philosophy. Ten years later, I was embarrassed by them. You might be, too.</p>
<p>Unless I had a really good reason (and “sharing” isn’t one of them), I wouldn’t post anything online. If you want to “share”, do it via PM.</p>