Mars trips may involve less radiation exposure than previously thought:
There's no question that the first human mission to Mars will be extremely dangerous. Some studies have suggested that the radiation levels would exceed the maximum career dose for a given astronaut, greatly increasing the risk of cancer and other illnesses. It might not be quite so bad as it sounds, though. Newly presented ESA ExoMars orbiter data indicates that astronauts would receive "at least" 60 percent of their maximum recommended career radiation exposure on a round trip to Mars that takes six months both ways. That's still several times what ISS crew members receive, but it's relatively gentle compared to what some had feared.
(Score: 2) by Immerman on Thursday September 20 2018, @09:35PM (5 children)
It also applies to believing something *without* evidence. The distinction is extremely important to scientists, and there's not really a term specific to "belief without evidence" (faith has far too many other implications)
Look at the Venn diagram on the page if you need clarification. Belief has no relationship with facts. If you want to say something is "true", saying that you believe it is irrelevant. Knowledge has supporting evidence, belief is... just belief. It's a statement about your personal framework, not about the universe.
Or to put it another way,
Saying that you know something means you believe it *and* have solid evidence to support that belief.
Saying you believe it is a much weaker statement which, by virtue of not making the stronger claim, implies that you *don't* have solid supporting evidence.
(Score: 0) by Anonymous Coward on Thursday September 20 2018, @09:46PM (4 children)
How do you know you arent living in a simulation, etc and everything is an illusion? You don't know for sure, some people think its 1 billion to one odds this isnt a simulation:
https://www.independent.co.uk/life-style/gadgets-and-tech/news/computer-simulation-world-matrix-scientists-elon-musk-artificial-intelligence-ai-a7347526.html [independent.co.uk]
We never "know" anything for sure, there is only belief.
(Score: 2) by Immerman on Thursday September 20 2018, @10:07PM (3 children)
Sure, which makes the question irrelevant. That's philosophy, and the philosophers can sit around mutually mentally masturbating over the issue until they all crumble to dust. I wish them much satisfaction of it, but unanswerable questions are explicitly outside the realm of science. It's not even a new idea - just a rehashing of Descartes Evil Demon Hypothesis from almost 400 years ago, with flashy new cyberpunk paint job. Or Plato's Allegory of the Cave, from almost 2000 years before that. That's the problem with unanswerable questions - you can keep rehashing them over and over again for, literally, thousands of years, and get not one iota closer to an answer.
Do we have evidence that this *isn't* a simulation? No - just like we don't have any evidence that there *isn't* an giant invisible teapot orbiting the moon. It is logically impossible to disprove the existence of something. But in the absence of evidence in support of such a conjecture "the universe is as it appears to be" is the default, useful, assumption. And science is all about practical, confirmable results. It's not trying to reveal the ultimate nature of reality - it's trying to fully, accurately describe how the natural universe behaves.
(Score: 0) by Anonymous Coward on Thursday September 20 2018, @10:19PM (2 children)
The point was that there is nothing you actually "know", so no one should even use that term except in a religious context.
(Score: 2) by Immerman on Thursday September 20 2018, @10:48PM (1 child)
You absolutely should *not* use the term in religious contexts - by and large there are no facts to support religious assertions, it's pure faith. And without testable facts, you have only belief, not knowledge.
Facts meanwhile are the raw data about which everyone (intellectually honest) can agree upon. Everyone can agree that rocks are hard - if you deny the evidence of your senses (aka the natural universe) then you have no basis for building knowledge at all. You'll be in the grip of Descartes radical doubt, and cogito ergo sum is the *only* thing you can ever know. Even he could not endure that and jumped down a series of very questionable assumptions to escape back to a belief in the natural universe.
(Score: 0) by Anonymous Coward on Thursday September 20 2018, @10:59PM
So you "know" we don't live in a simulation then? If billionaires and scientists are trying to "break out of the simulation", it doesn't sound like a self defeating belief to me...