How Scientific Progress Is Made
Science is not inerrantly accurate, among other reasons because there is always a degree of inaccuracy in empirical observation, not to mention the potential to misinterpret those observations. Science is the set of procedures and techniques that we use to increase the accuracy of the theories we use to explain the world. Every step forward isn't a "retraction" as much as a "refinement". That's why formerly accepted theories are superseded rather than falsified. Like when you throw out your NTSC television after buying a 1080p plasma. The old tv wasn't "wrong", it's just obsolete. That's progress. That's how it is, and that's how it should be.
Linnaeus gets credit for taxonomy even though he didn't understand that the structure was due to evolution. Darwin gets credit for evolution even though his theory didn't account for genetics. Mendel gets credit for genetics even though his theory didn't account for nucleotide sequences. Watson and Crick get credit for nucleotide sequences even though they didn't account for reverse transcription. Progress is marked by progressive refinements - "pushing the ball forward" - rather than absolute accuracy. And because the ball is always being pushed forward, we're always approaching better accuracy, and this happens by superseding old theories with better ones. Even the textbook "failures" weren't actually failures: Alchemy begat chemistry. Phlogiston begat oxidation and combustion. Plum pudding begat Rutherford begat Bohr begat the electron cloud which begat QED. Newtonian Mechanics begat special relativity which begat general relativity. Superseded theories become the foundation for the scientists who built even better theories upon them. Keep pushing the ball forward.
"The scientist is a practical man and his are practical (i.e., practically attainable) aims. He does not seek the ultimate but the proximate. He does not speak of the last analysis but rather of the next approximation. His are not those beautiful structures so delicately designed that a single flaw may cause the collapse of the whole. The scientist builds slowly and with a gross but solid kind of masonry. If dissatisfied with any of his work, even if it be near the very foundations, he can replace that part without damage to the remainder. On the whole he is satisfied with his work, for while science may never be wholly right it certainly is never wholly wrong; and it seems to be improving from decade to decade." - G. N. Lewis. Quoted in Stochiometry by Leonard K. Nash. Addison-Wesley 1966. p. vii.).
At this point, shrewd (or argumentative) readers will ask what exactly I mean by "wrong". "If phlogiston wasn't wrong then what was?" Phlogiston was thought to be "elemental fire" which was released when an object burned - wood minus phlogiston equals ash. That's not entirely wrong if you consider that phlogiston is just combustion backwards: they took the right idea in the wrong direction. Oxygen is "elemental fire", but it's bound to the substance not released from it - wood plus oxygen equals ash/CO2. Even so, there are a few theories which are just plain wrong from the start. The aether was always total bunk. It was an untested assumption - nobody had actually verified that the aether existed, until Michelson and Morley showed that it didn't. And that's where the greatest potential for mistakes seems to be; not in the claims themselves, but in the untested assumptions. The stuff that makes its way into the scientific community without testing or peer review. Fortunately scientists understand this; the process of peer review subjects theories to scrutiny, with significant incentives for anyone who uncovers such an assumption. And that's the real strength of the scientific community:
In science it often happens that scientists say, 'You know, that's a really good argument; my position is mistaken,' and then they actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. - Carl Sagan
This post is addressing what I see as a broader misunderstanding that crops up from time to time. I'm posting this here so that I can refer to it later.
Linnaeus gets credit for taxonomy even though he didn't understand that the structure was due to evolution. Darwin gets credit for evolution even though his theory didn't account for genetics. Mendel gets credit for genetics even though his theory didn't account for nucleotide sequences. Watson and Crick get credit for nucleotide sequences even though they didn't account for reverse transcription. Progress is marked by progressive refinements - "pushing the ball forward" - rather than absolute accuracy. And because the ball is always being pushed forward, we're always approaching better accuracy, and this happens by superseding old theories with better ones. Even the textbook "failures" weren't actually failures: Alchemy begat chemistry. Phlogiston begat oxidation and combustion. Plum pudding begat Rutherford begat Bohr begat the electron cloud which begat QED. Newtonian Mechanics begat special relativity which begat general relativity. Superseded theories become the foundation for the scientists who built even better theories upon them. Keep pushing the ball forward.
"The scientist is a practical man and his are practical (i.e., practically attainable) aims. He does not seek the ultimate but the proximate. He does not speak of the last analysis but rather of the next approximation. His are not those beautiful structures so delicately designed that a single flaw may cause the collapse of the whole. The scientist builds slowly and with a gross but solid kind of masonry. If dissatisfied with any of his work, even if it be near the very foundations, he can replace that part without damage to the remainder. On the whole he is satisfied with his work, for while science may never be wholly right it certainly is never wholly wrong; and it seems to be improving from decade to decade." - G. N. Lewis. Quoted in Stochiometry by Leonard K. Nash. Addison-Wesley 1966. p. vii.).
At this point, shrewd (or argumentative) readers will ask what exactly I mean by "wrong". "If phlogiston wasn't wrong then what was?" Phlogiston was thought to be "elemental fire" which was released when an object burned - wood minus phlogiston equals ash. That's not entirely wrong if you consider that phlogiston is just combustion backwards: they took the right idea in the wrong direction. Oxygen is "elemental fire", but it's bound to the substance not released from it - wood plus oxygen equals ash/CO2. Even so, there are a few theories which are just plain wrong from the start. The aether was always total bunk. It was an untested assumption - nobody had actually verified that the aether existed, until Michelson and Morley showed that it didn't. And that's where the greatest potential for mistakes seems to be; not in the claims themselves, but in the untested assumptions. The stuff that makes its way into the scientific community without testing or peer review. Fortunately scientists understand this; the process of peer review subjects theories to scrutiny, with significant incentives for anyone who uncovers such an assumption. And that's the real strength of the scientific community:
In science it often happens that scientists say, 'You know, that's a really good argument; my position is mistaken,' and then they actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. - Carl Sagan
This post is addressing what I see as a broader misunderstanding that crops up from time to time. I'm posting this here so that I can refer to it later.