Last Thursdayism (sometimes Last Tuesdayism or Last Wednesdayism) refers to the idea that the universe may have been created last Thursday, but with the physical appearance of being billions of years old. Under this notion, people’s memories, history books, fossils, light already on the way from distant stars, and so forth would all have been formed at the time of creation (last Thursday) in a state that causes them to appear to be older. It forms both a philosophical point about how our observations may not match with “reality” and a reductio ad absurdum of some young-Earth creationist ideas; if the world was created 6000 years ago with the appearance of being made billions of years ago, what stops us simply claiming it was made last Thursday in the same manner?
The “Last Thursday” variety is a parody of the omphalos hypothesis, and a relative of Bertrand Russell’s equally parodic five minutes ago hypothesis. (1)
The problem with this hypothesis is that it is not “scientific” because it is not
“falsifiable”. (2) This is one of the most important conditions a theory must meet – according to Popper – in order to be considered “scientific”.
But wait a minute…
Why should one even care about that?
Why should we care about something being able to be disproved? Couldn’t something correct not be falsifiable? Why should we care if something is called “scientific” anyway?
The answer is simple: There is no reason at all!
Most people want and hope what they say is “scientific” only because science is the new religion of our times. And everybody likes adhering to the religion of their times…
Some might say that something must be scientific if we want it to be useful and help us with predicting things as science does. But the most important things governing your life are unpredictable. (like love for example) The most important breakthroughs in science have come through “unscientific” theories which are not falsifiable (see the multi-universe interpretation of quantum theory or the theory of evolution or the theory which talks about an ever-existing universe for example). And all in all, some of the most important theories in human history are simply… not even scientific! They are philosophical and they are proud of it! (like the theory of Schopenhauer about Will and Existence or the “theory” – if you call it that way – of a man called “Christ”)
Look for your compass.
Then break your compass.
It will be the best compass you ever had…