The philosopher Ernst Bloch writes that some false propositions “are not totally finished with regard to the truth.” This strange formulation insists that factually untrue philosophical propositions are not doomed to remain untrue forever. He gives the example of Socrates’ proposition that nobody voluntarily does wrong. This, of course, is wildly untrue. Last summer someone stole my identity, and I’m sure the thief knew it was wrong to buy all those iPads on the Sam’s Club credit card fraudulently opened in my name. But Socrates tries to make this point: lack of virtue comes from ignorance, but because virtue comes from knowledge, it can be taught and acquired. If one acquires virtue, one would not voluntarily (i.e. knowingly) do wrong. How sanguine should this make us about the future?

The way we respond to the idea that false propositions might have business with the truth in the future has a lot to do with how we view human nature. If human nature is static, universal virtue seems beyond us. An English professor’s social security number will always be too great a temptation for some potential malefactors to resist exploiting it.

But what if, like Bloch, we were to imagine that human nature is not yet determined, that humans are still living in prehistory? What if human nature is still totally up for grabs? This view sees the future as open to possibility.

Some things argue in favor of this counterintuitive view. The Declaration of Independence says, “We hold these truths to be self-evident, that all men are created equal.” As with Socrates’ proposition, counterfactual examples abound. When Thomas Jefferson wrote this famous phrase, slavery, patriarchy and class hierarchy belied its truth. Contemporary forms of discrimination show that we still do not all believe that everyone deserves equal treatment and opportunity. If human nature is fixed, we must conclude that it is our nature to enslave, discriminate against or subordinate the less powerful.

But I think this discounts the transformative power of a good progressive idea. The changes that progressive ideas can provoke give some respectability to the view that human nature is still up for grabs. American history (or prehistory) has substantially made the Declaration of Independence’s proposition incrementally more, if still imperfectly, true. I believe that ideas can change human nature and that progressive ideas can improve it.

I’m not so optimistic as to say that the right ideas will necessarily change us. Progress is tenuous — wars and other catastrophes can destroy it, bad ideas can roll it back — but good progressive ideas are also more tenacious than we sometimes think. In daily politics, progressive ideas seem fragile, and when it comes to everyday human experience and quality of life, they are. However, progressive ideas also spread on a longer timeline. Martin Luther King, Jr. was right when he said, “I may not get there with you.” In fact, none of us may be there when it happens, but this is merely the cruelty that comes from the slow advancement of progressive ideas relative to the brevity of individual lives. It ought to provoke sobriety and resolve rather than despair.

Take vegetarianism. Last semester there was debate in these pages about whether or not we should be vegetarians or vegans. We might look at history (or pre-history) and conclude that it is natural to eat non-human animals. But it took until the 19th and 20th centuries for the modern idea of vegetarianism to emerge in the west. It is still a relatively infant idea, and it was hardly inevitable that the concept would ever have emerged as it has. Now that it has caught on with many people, for varied reasons (health, ethics, religious discipline and so on), it puts pressure on the idea that people naturally eat animals or that we can justifiably continue to view animals as instrumental means to human ends.

The next thing we have to think about is possibility. Bloch insists that our picture of reality is incomplete if it excludes anything that could conceivably happen, however unlikely. It may have been unlikely that slavery would have been abolished, or that women would achieve many (but not yet all) forms of equality, or that all Americans would enjoy marriage equality. Yet these things were perfectly possible and they did happen.

So let’s continue our thought experiment about vegetarianism and animal equality. It might be unlikely, but it is perfectly possible that humans will stop killing animals and begin to view the value of animal life as equal in worth and dignity to human life. It is possible that in 200 years, as we now regard the barbarities of slavery, humans will look back at meat-eaters as barbarians, and they might understand factory farming as institutionalized murder on an almost inconceivable scale. Because this is perfectly possible, we must recognize that this real possibility is part of our current reality. Such recognition generates the wish images that give life to our hopes and struggles.

Things get nudged ahead or retarded by executive orders in the short term, but good progressive ideas have a certain staying power and are capable of changing the basic terms with which we understand ourselves. Outcomes are never assured, so people continue to fight, protest and resist, but currently false propositions sometimes have dates with truth in the future. We should also recognize that many of our existing progressive ideas are imperfect, and that this might be part of their relative failure to date. We need to look forward to the new and better progressive ideas yet to be discovered in the work of future artists, philosophers, scientists and others. If the right ideas can change human nature for the better, then openness to progressive ideas may be a step toward Socratic virtue and may simultaneously make Socrates more truthful than he is today.