The notion of ‘nishtanu ha-teva’im’ (‘nature has changed’) as an explanation for why ancient (and not-so-ancient) Rabbinic statements about the natural world don’t corroborate modern scientific understandings and observations has gotten a lot of press recently, and, let’s face it, it seems pretty weak.
I wanted to try to understand the idea in a different way, which perhaps will make it appear a bit less naïve and/or delusional.
Everybody has certain incipient understandings about the way the world works. As we grow up, it changes (hopefully) to reflect our education and understanding. The key question about it is this:
When understandings about the world change (or undergo what Thomas Kuhn calls a paradigm shift), what exactly changes?
What most of us would respond right away is that the world obeys the same laws that it always obeyed, but that our minds have come closer to apprehending the truth of those laws.
This response reflects a bias that the human mind is capable of constructing a completely representative model of the world inside itself. Beginning with Kant’s Critique of Pure Reason (though perhaps beginning with Hume), this bias has been shown to be inadequate. The human mind can’t apprehend the world as it really is. The laws of nature themselves are not objective realities, but patterns which our minds impose upon observed phenomena. We inhabit the world that our minds and cultures construct for us. That world has rules. But the rules are part of the world as we perceive it, not of the world as it objectively is (NOTE: as Kuhn would often point out, this doesn’t mean that all of science is ‘subjective’ in the sense that it’s arbitrary and the result of personal whim. Rather, it means that it’s a very real reality which presents itself to the observer. Call it an ‘aspaklaria she-einah me’irah if you will).
Thus, in a paradigm shift, it’s not only the observer’s mind which ‘changes’, but it’s an entirely different world which the observer now inhabits. It’s like those 3-D illusion pictures – by looking at it in a different way, you’re actually looking at an entirely different picture.
So perhaps that’s what ‘nishtanu ha-teva’im’ means: scientific revolutions have determined that we occupy what’s actually a differently constructed world, with different rules and laws. Nature itself has ‘changed’ – it presents itself to us in an entirely different way, and can’t be called the same ‘nature’. Earlier paradigms, which have been replaced, were as real to their adherents as contemporary ones are to us. Our predecessors constructed worlds out of them. Their laws reflect not only their ‘understanding’ of the world, but their ACTUAL world.
The task falls to us, who essentially occupy a different world, to find a way to translate from their world into ours. We also must face the reality that a lot will be lost in translation. ‘Nishtanu Ha-Teva’im’ is an acknowledgement that we occupy a different world, but are not absolved from engaging theirs.