illustration (attribution, if any possible, is at the end of the article)
Of course the Past contributed to conditions from which the Present arose… but this is not an 'explanation': it links an ineffable reality to another ineffable reality. The explanation arises when we try to 'explain'… but the past doesn't explain, we do!
The way the Present creates the Past is born in our present anguish and desire to find handles to make reality conform to our wishes… and how this present anguish leads us to presently create a narrative justifying our importance in the world and why other phenomena should comply.
Feeling secure? You're not too concerned with 'history'…
Feeling insecure, e.g. because someone claims the land you consider your own? You suddenly come up with History, an 'explanation' about how your ancestors have always been here, and how that gives you precedence, etc. As you well know that precedence hardly is enough (does a first crime left unpunished 'justify' all other similar crimes?), you also come up with the 'history' that civilisation co-dependently arose with the notion of 'propriety' and 'ownership'… and that, of course, this is 'progress', hence not to be challenged… You well know that as a situation evolves, adaptation to prior circumstances doesn't mean adaptation to current circumstances, but you'll still try to convince the other! That's a present narrative, aimed at attaining a present goal.
A way to see this is to see how the 'history' changes when a prior version didn't convince.
Someone wants you to move your car so they can park. They come angry at your door, wrapped in their righteousness and legitimacy, and instead of simply asking you to move your car, they'll go on and on about how long they travelled, their fatigue, their rights… to try to coerce you into giving them satisfaction.
The Present isn't explained by the Past, their present desire leads to an 'explanation' of the Past in an attempt to control the world and avoid its unsatisfactoriness! So they assume that e.g. speaking of their 2-hours drive gives them legitimacy and is therefore relevant… But what happens if you then say "Well, I just drove 4 hours" ? Suddenly, the history switches to something else, e.g. their partner is sick… But if your own sickness is 'worse' than their partner's, then it might switch to some 'right' they have, etc.
What's "relevant" has nothing to do with the Past, it has to do with what allows to convince the other person that you have priority in getting your desire fulfilled! The present desire creates the Past! [When it's not about convincing, it's about understanding, i.e. about gaining levers that could be used in the future to force reality to comply with one's wishes… maybe by such overwhelming causality that discussion and convincing wouldn't even be needed ;-) ]
Not only the present intention creates the Past, but also the present preferences for discourse modes: if there's a present tendency to value science, the 'history' might be framed in 'scientific' terms… but if the present preference is spiritual, the 'history' might be framed in terms of e.g. 'destiny' or "God-given right"!
What's "relevant" has nothing to do with the Past, it has to do with what allows to convince the other person that you have priority in getting your desire fulfilled! The present desire creates the Past, the present cherry-picking creates the Past, distinguishing what's relevant and what's not in ad hoc manner: change the present conditions and what's "relevant" will change ;-)
And thus explanations are not found in the Past. « This is therefore to say [It Starts Now - Alan Watts] … [the (past) Universe] is trailing off like the wake of a ship from now and as the wake of the ship fades out, so does the past. You can look back there to explain things but the explanation disappears. »
Our present explanations might be framed in terms of land, in terms of culture and of traditions, in terms of biology, in religious terms… But if you see the emptiness of the narrative, you can have a laugh at it! Great story, hugely entertaining; no need to cling to it as if it were the truth!
Whether you believe in some religious story of the Creation, or you believe in e.g. Darwinism, it's all a present creation of the Past, biased by present preferences regarding what forms of language gives more legitimacy…
How does it give you any 'legitimacy' that your ancestors were early, incestuous, ignorant murderers… or some sort of monkeys? It doesn't!
Do you buy into "I know who I am, because I know my ancestors were monkeys"? Really? Do you buy into "This is my land, because my ancestors were here first" ? Really? This is just you trying to get a handle on reality now, when someone is here with you, when reality is asking you an answer but you'd prefer them not to be here, you'd prefer life to be 'different'!
The above is critical about one buddhist teaching: karma.
Karma refers to intentional tendencies, and to causality based on intentional tendencies. Can intentions, in particular repetitive intentions (that might lead to embodiment), lead to consequences? Of course. Does this mean that everything requires "past intentional tendencies" to be part of the explanation? Of course not!
The present anguish while facing the ineffability of the world, while facing our lack of satisfactory knowledge of the world, our not-knowing, our inability to predict, our inability to control with certainty… lead some to create reassuring (but ignorant) 'certainties', by way of a deterministic version of karma.
But the Past doesn't explain the Present. And the buddha explained that karma is not deterministic, and also is intractable (which isn't surprising since there's no inherent unchanging 'self' —even as a trackable 'process'— to which it could be attached!). One of the reasons karma isn't deterministic is that "cause–effect" relationships arise in context-dependent manner (note: this is why we can free ourselves from past karma… by cultivating wholesome contexts and circumstances, in which past karma will ripen but without automatically causing perpetuation or even suffering), i.e. conditions and seeds are empty of 'condition' / 'seed' essence (see chapter 1 of Nāgārjuna's Mūlamadhyamakakārikā if interested).
Using karma to justify disability isn't understanding karma. It's to confuse engagement and outcome. When such conceited speech is given, if anything, the tendency that is visible isn't the one of the disabled person… but the one of the 'explainer' (who clings to certainties and wants the world to be 'explained', with clear labels, no matter what, even if it's via blaming victims!).
Maybe the disability is a karmic result… but you don't know that! So don't pretend it's known, don't pretend it's sure, based on some quote from the Buddha (when you cannot even be sure he actually said such a thing!), some argumentum ab auctoritate, or simply some argumentum ad ignorantiam.
What is the compassionate, loving, equanimous response you'll give to the present situation? That's the question! Even if the disability were a karmic result, the question would still be about your response to the situation at hand, not about whether you can 'explain' the disability!
Will you move your car, with a welcoming smile to the person who requested so, or will you start a debate about who's more 'entitled' to the parking spot?
photo: boat sailing the Lyse fjord in Norway, by Edmond (on wikipedia)